HRV and Strength Research: Implications for Strength/Power Athletes?

At this point there is quite a bit of research pertaining to HRV and aerobic exercise/endurance training. However, the application of HRV for strength/power (S/P) athletes is less clear. Today I will discuss the available research pertaining to resistance training (RT) and HRV and share some of my thoughts on the topic.

Unfortunately for S/P athletes, the majority of the research that exists involving RT and HRV do not involve athletes. Rather, most of the research tests the effects that RT has on resting HRV for the purposes of improving health/reducing mortality in elderly or diseased populations. Nevertheless, I will summarize what I’ve read.

Heffernan and colleagues (2007) found no change in HRV following 6 weeks of RT and after 4 weeks of detraining in 25 year old male untrained subjects (n=14).

Cooke and Carter (2005) saw non-significant increases in HRV following 8 weeks of RT compared to control in healthy young adults (n=22).

In middle aged folks with pre-hypertension, aerobic exercise increased HRV while RT resulted in decreases in HRV (Collier et al. 2009). In healthy young adults aerobic training improved HRV (in men but not women) while RT had no effect (Sloan et al. 2009).

Elite endurance athletes had higher HRV at rest compared to Elite power athletes but the power athletes had better resting HRV than control (Kaltsatou et al. 2011). No surprise here.

Following 16 weeks of resistance training, a high intensity group and a low intensity group of healthy older women both improved strength with no significant changes in HRV (Forte et al. 2003). These results were consistent with findings by Madden et al (2006) with the same population however they included an aerobic training group who did see increases in HRV.

RT improved HRV in women with fibromyalgia in a study by Figueroa et al. (2007) but failed to improve HRV in the same population in work by Kingsley et al. (2010).

Compared to 3 months of low intensity training (calisthenics and breathing training), intense training (combined aerobic and strength training) improved HRV at rest and in response to orthostasis (standing) in COPD patients (Camillo et al. 2011). The researchers found that better baseline HRV, muscle force and daily levels of activity were predictors of HRV changes after exercise intervention.

In healthy older men, 12 weeks of eccentric RT resulted in decreased HRV. (Melo et al. 2008)

If one’s goal is to increase HRV via exercise then I would definitely go with aerobic work as this seems to be more effective than RT, though the results are conflicting. Training protocols, subjects, health status, age, HRV measurement position and duration, etc. all vary quite a bit which likely accounts for the conflicting results. I assume that there is a volume/intensity threshold that must be met during RT periods to cause a change in resting HRV. For optimal health it is likely that a combination of aerobic work and RT will offer the most benefits.

From personal experience, I see much higher scores when I incorporate more aerobic or intermittent conditioning work. In reviewing my all time HRV trend, I can clearly see that over the spring and summer (03-09) of 2012 I had considerably more green scores and higher deflections. This is in line with the time that the weather got nicer and I started doing 30-40 minute runs 3-4x/week (March was unusually warm last year). I got really sick for 2 weeks in June as I discussed here, otherwise I would expect  my trend to be even higher. Once Sept. rolled around I started working full-time again and reduced my aerobic work to 2x/week for about 2o minutes and at a lower intensity at which point baseline declines back to pre-spring/summer levels.

trendalltimejan28

Implications for S/P Athletes

The application of HRV for S/P athletes is obviously different than for elderly or diseased populations. RT is incorporated in training as a means to increase performance, not to increase vagal tone. Therefore, the utility of HRV for this population revolves around its potential ability to:

(Any research I discuss in this section has been cited previously and will not be cited again today, see my older posts for references.)

  • Predict training outcomes

–       Higher HRV at baseline results in improvements in aerobic performance (see here). Would higher baseline HRV result in better S/P improvements? If so, would purposeful manipulation of ANS prior to intensive RT periods via “aerobic” (read “work capacity”) training be of benefit? We already know the importance of GPP but is this relationship mirrored in HRV? If so, HRV may be worth monitoring during these periods.

–       Better basketball and ice hockey performance as well as endurance performance has been correlated with HRV (specifically parasympathetic tone) as I’ve discussed in previous posts. I’m not sure this relationship exists with S/P athletes but it would still be worth testing. Anecdotally, I’ve experience reduced strength performance when HRV is low due to physical fatigue. However, I haven’t really seen strength affected when HRV is low caused by other factors (sleep, other stressors, etc.) Therefore, establishing this relationship must involve careful consideration of these variables.

  • Reflect Recovery Status/Training Load, Overreaching/Non-Functional Overreaching

–       Does overreaching in S/P athletes result in a concomitant decrease in performance and HRV?  Elite female wrestlers were considered non-functionally overreached when performance decreased and HRV was significantly above or below baseline for greater than 2 weeks. Elite tennis players saw significant decreases in HRV but improved performance. Generally in endurance athletes, overreaching will result in decreased performance and a significant increase or decrease in HRV (from baseline).

–       I feel that in S/P athletes, performance probably won’t decrease concurrently with HRV assuming it is a gradual decline as a result progressively increasing training loads. Rather, HRV will probably change first indicating an accumulation of fatigue and performance will fall at some point after if loading persists. Monitoring HRV may be useful to prevent excessive fatigue/overreaching if that isn’t the goal. Perhaps it is also useful in detecting transitions from functional to non-functional overreaching (the point at which HRV changes from overly sympathetic to highly parasympathetic).

–       Does the return to baseline HRV (after overreaching) happen concurrently with return or increase in S/P performance? This was the for case elite swimmers as peak performance occurred concurrently with peak HF values (parasympathetic tone). If so HRV would be a good tool for guiding tapers and establishing best protocols for meet/competition preparation.

–       HRV is an effective tool for guiding aerobic training. Does this apply to S/P athletes? Given that HRV reflects recovery status in S/P athletes (both in the research and anecdotally) and that HRV is sensitive to pretty much all forms of stress, it would seem logical to at least consider HRV in determining daily training. HRV may serve as a guide for determining training frequency and intensity/volume based on individual recovery. More on this topic here. It would be interesting to see HRV guided vs. Pre-planned RT compared in S/P athletes.

  • Guide Periodization

–       HRV will decrease in response to an intense workout. When you perform that workout again and again, your body adapts. The workout is no longer as stressful (decrease in soreness, lack of HRV response, quick recovery, etc. What benefits can HRV offer for adjusting volumes, intensities, exercise selections, frequencies etc. in effort to continually stimulate progress? Is HRV response after a workout any indication of how effective that workout is? Of course there are other factors to consider, not just the amount of stress/fatigue a workout causes. I have repeated workouts with high perceived exertion that have had little effect on HRV. Does that indicate that a change is needed in programming?

It goes without saying that several other factors and variables should be considered when analyzing HRV. HRV is only one variable and is sensitive to a variety of factors that  can influence a result (non-training related stressors, pre-competition anxiety, etc.).

Announcement

This March I will be relocating to Alabama to work in the Human Performance Lab at Auburn University (Montgomery campus) with Dr. Mike Esco. I met Dr. Esco at the NSCA National Conference in RI last summer. Dr. Esco has been researching HRV for several years now. We have several projects tentatively planned and doing an HRV and RT study is one that we’ve been considering. Hopefully we can make it happen.

References

Camillo, C.A. et al. (2011) Improvements of heart rate variability after exercise training and its predictors in COPD. Respiratory Medicine, 105(7): 1054-1062

Cook, W.H., & Carter, J.R. (2005) Strength training does not effect vagal-cardiac control or cardiovascular baroreflex sensitivity in young healthy subjects. European Journal of Applied Physiology, 93: 719-725

Forte, R. et al. (2003) Effects of dynamic resistance training on heart rate variability in healthy older women. European Journal of Applied Physiology, 89: 85-89

Heffernan, K.S. et al. (2007) Heart rate recovery and complexity following resistance exercise training and detraining in young men. American Journal of Physiology – Heart & Circulation Physiology, 293: H3180-H3186

Kaltsatou, A. et al. (2011) The use of pupillometry in the assessment of cardiac autonomic function in elite different type trained athletes. European Journal of Applied Physiology, 111: 2079-2087

Kingsley, J.D., et al (2010). The effects of 12 weeks of resistance exercise training on disease severity and autonomic modulation at rest and after acute leg resistance exercise in women with fibromyalgia. Archives of Physical Medicine & Rehabilitation, 91: 1551-1557

Madden, K.M. et al. (2006) Exercise training and heart rate variability in older adult female subjects. Clinical & Investigative Medicine, 29: 1 – ProQuest

Melo, R.C. et al. (2008) High Eccentric strength training reduces heart rate variability in healthy older men. British Journal of Sports Medicine, 42: 59-63

Sloan, R. P., Shapiro, P.A., DeMeersman, R.E., Bagiella, E., Brondolo, E., McKinley, P.S., Slavov, I., Fang, Y., & Myers, M.M. (2009). The effect of aerobic training and cardiac autonomie regulation in young adults. American Journal of Public Health, 99(5), 921-928

Reflections, Thoughts & Some HRV Data Analysis from 2 Athletes

This week Carl Valle had a great article posted on Mladen’s site here. It’s definitely worth the read if you train athletes. This article inspired me to reflect on where HRV fits in to training, for whom it may work best for and why. I monitor HRV in a very small number of athletes who are the minority of the overall pool of athletes I work with.

To get the most out of HRV tracking, I believe it should be measured daily, in the morning after waking. With ithlete this requires less than 2 minutes of your time to perform the measurement and make any comments, input training load, etc. Though this is a simple task, it is not easy to get full compliance from individuals. Therefore, I don’t even consider getting an athlete taking measurements unless he possesses a great deal of intrinsic motivation, is responsible, reliable, and perhaps most importantly, is interested. Though I would prefer they know nothing about the device, it’s hard to convince people to commit to using it every day if they don’t understand why. After a few sessions I will mention it to them and give them some basic details. If they appear interested or ask if they can use it then it’s a go.

I have several motivations for tracking HRV in select athletes. Below, these motivations are listed with some follow-up thoughts and elaborations.

  • To observe ANS response to training, daily stressors, recovery modalities, etc.

What was HRV score the day following a workout? What else did the athlete do that day that may influence this score? What has the overall trend been that week (positive or negative)?  I like to compare HRV score to other training status markers like strength levels (did he hit target weights for the day?), movement ability (how does he look during warm-ups, jumps, etc.?), perceived recovery/readiness levels (Does he feel great when HRV is high, when its low?), etc.

This motivation serves two purposes.

  1. It gets the athlete more engaged in his life style and training (more on this in a bit)
  2. It satisfies my curiosity. I’ve got questions I want answered.
  • To observe HRV trends over times of illness, injury, etc. to determine if there were early warning signs in the trend and if the trend reflects recovery/return to play readiness.

In the event of an injury during practice or competition, what was the trend indicating? In the past year or so I hurt myself once during training and it happened with 60% of my 1RM during squats (hardly a threatening situation). My HRV that day was well below baseline. Possibly a coincidence, or possibly injury risk is heightened when HRV is really low. To my knowledge, there is no research on this in human athletes, but this seems to be the case in race horses. I discussed some very interesting research by Dr. Christine Ross in this post from last winter.

Here’s an excerpt from that post.

“Dr. Christine Ross monitored the HRV of 16 competitive race horses, all of which were in training. Of the 16, 13 had HRV readings that were associated with pain, fatigue, illness or injury. It was stated that even though the horses appeared healthy and energetic, they were considered “at risk” based on their HRV. There were no outward signs or symptoms to suggest these horses were currently sick or hurt. Within 3 months, 12 of the 13 at-risk horses got injured or sick requiring veterinary intervention and cessation of race training.”

Furthermore, I work with plenty of football players and hockey players who by nature are at risk of concussion. What insight can HRV provide regarding recovery and return to play after concussion? (Perhaps a post on this in the future)

  • In rare cases, to manipulate training if HRV has been consistently below baseline and the athlete displays signs of fatigue.

This is an interesting topic. Working with an athlete is rarely long term. In many cases you may only have 6-8 straight weeks of consistent training before interruption. That means we need to get them better quickly. Getting better can be defined in many ways but in the training realm this means improving strength, speed, power, work capacity, etc. To do this we need to apply stress. In some cases, a lot of stress, of various kinds. Naturally, HRV will drop. The organism has to work hard to adapt to the stress (and thus improve). We don’t have time to wait for “optimal” recovery and this is likely not even desirable.

Let me use an example. Below is the HRV trend of a 25 year old hockey player I’m working with. He’s come to me to get in shape for a try-out he’s been invited to for a pro team in Germany.

A.E.Trend

He is a former NCAA hockey player and has been training relatively consistently throughout school. After this summer he thought he was done with competitive hockey and stopped training however he did start playing men’s league hockey.  Since he hasn’t been training I knew we’d probably see some pretty big downward deflections after our first few workouts. He missed a few mornings of HRV measurements but it’s been about 2 weeks since we started. The “week change” is -8 and his HRV trend is steadily decreasing. His strength is steadily improving as is his conditioning. He’s adapting fast and re-acquiring lost strength and fitness. Training loads are steadily increasing every week. Now that it’s Christmas I expect to see his HRV bump back up due to some extra rest and likely extra calorie intake. So long as HRV approaches baseline levels after a few days of rest then I think things are looking good. However, if HRV continues downward I will evaluate performance markers and make adjustments if necessary. The physical stress load is high as reflected by his HRV but it’s only been 2 weeks and his performance markers are improving. The weekly trends will likely continue to decrease until about 2 weeks out from the try-out at which point I’ll steadily reduce loads. HRV should climb back up and fatigue should dissipate. This is what happens when I have a relatively short period of time to work with an athlete.

In contrast, the trend below is of a high school sprinter I’m working with. He trains with his sprint coach and works with me for recovery/restoration, mobility, etc. He has a sub 11s 100m time and is one of the fastest high school sprinters in Canada. He is much more long term and his training load reflects that. His weight training volume has been reduced quite a bit and has transitioned into more sprint work and power development in the weight room (controlled and implemented by his Sprint Coach).

ZW Trend

This is an athlete who takes care of himself and is extremely motivated to get better, to say the least. He reports that training is going well, he’s hitting PR’s and it looks as though he’s handling training almost too well. Higher loads would be likely well tolerated. If I can just start getting him to get to bed at a decent hour on weekends he’ll be doing everything right.

In both cases the athletes have learned how lifestyle factors outside of training effect their recovery, soreness levels, etc. This is directly attributed to seeing their HRV trend, recognizing what events may have caused the additional stress and re-evaluating there decision making. One of the main things I like about HRV is that it forces you (and the athlete) to be more engaged in the process. It allows them to see how their actions (good or bad) can effect the quality of their training and their progress.

Final Thoughts

Having HRV records as an objective measure of training status helps guide the training process when taken with other markers of performance and fatigue. If the athlete is a high level athlete, mature enough to handle daily measurements and wants to use it then I am all for it. I don’t use it with many athletes because it would be a waste of time and energy for both parties. However, with the right athletes it can be a great tool to for monitoring training.

HRV Monitoring in a Team Setting: The Research

Though my original interest in HRV monitoring was for personal usage with my powerlifting training (and still is), I have become much more interested in its application with my athletes. In July, I wrote a post discussing some of the research and my thoughts on HRV in a team setting. I’ve come across some more great research that pertains to HRV monitoring in team settings and would like to share some thoughts on the topic.

Below is a  list of questions I’d like to address:

  • How effective is HRV monitoring in a team setting really?
  • What difference is there, if any, when monitoring HRV in elite vs. sub-elite athletes?
  • How practical is HRV monitoring in a team setting?
  • Can we create favorable autonomic profiles in athletes prior to intensive training blocks to improve global (all players) responsiveness to training? (to avoid injury, overtraining, etc)
  • How can we apply research that used frequency domain measures (HF, LF, HF/LF) with mobile apps/devices like ithlete and Bioforce that use RMSSD, a time domain measure of parasympathetic tone?

Keep in mind that I do not train elite athletes and therefore much of what I discuss is based on my interpretations of the research, discussions I’ve had with others and some theory. I certainly am not capable of providing answers to any of the above question.

First, I’d like to present brief summaries of the research I’ve read on the topic. I’ve only included studies that used HRV to monitor fatigue, training load, etc. At this time I’m not including studies using HRV during exercise, or post-exercise.

In some cases I could not get access to the full-text which you will see noted in the respective tables. Please enlighten me of any research on this topic I may have not included. I apologize for the poor presentation of the table’s below. I originally had all of this in a more reader friendly format in Word but for some reason it does not transfer over to wordpress very well.

Author Ke-Tien (2012)
Sport Male, National Level Rugby (n=24)
Aim To verify biological and psychological stress markers during strenuous cardiovascular endurance training periodization, using Profile of Mood States questionnaires, HRV & blood urine nitrogen as the criteria measurements.
Main Findings HRV correlated to profile of mood states survey and blood-urnine nitrogen in elite male national rugby players (n=24).
HRV Analysis Non-daily, Frequency Domain
Author Edmonds et al. (2012)
Sport Male, Elite Youth Rugby (n=9)
Aim To investigate the influence of weekly training & a competitive game on HRV in elite youth rugby league players, & to identify the importance of HRV as a monitoring tool for Rugby League player preparation.
Main Findings Prior to a match, elite youth, players exhibited a significant reduction in HRV that was sustained for at least 24 hours post-game. This withdrawal of parasympathetic &/or increased sympathetic control of HR possibly may result from pre-match anxiety as well as the physical demands of the game. Strong relationships between HRV and training load at Pre-2 indicate that early monitoring may assist in identifying training workloads for the upcoming week.
HRV Analysis Daily, Time & Frequency Domain
Author Oliveira et al. (2012a)  – Abstract Only
Sport Male, Elite Futsal (n=11)
Aim The aim of this study was to determine the changes in physical performance and resting heart rate variability (HRV) in professional futsal players during the pre-season and in-season training periods.
Main Findings Players improved their RSA & Yo-Yo IR1 performance with concomitant improvements in HRV. These indices were maintained during the in-season period while RSAbest was improved & RSAdecrement impaired. Frequent monitoring of these performances and HRV indices may assist with identification of individual training adaptations and/or early signs of maladaption.
HRV Analysis Non-daily, Unknown
Author Vantinnen et al. (2007)
Sport Male, Elite Soccer (n=24)
Aim To introduce a method commonly used in Finnish sport to monitor the exercise intensity & changes in recovery state of players in team sports by examining their heart rate (HR/HRV) responses to training & relaxation stimulus.
Main Findings Individual differences do exist in practices & games. This would imply that coaches need to quantify each game or practice exercise intensity & recovery for each individual, in order to organize & optimally prepare an individual training plan for each athlete.
HRV Analysis Various over 3 weeks (daily, nocturnal, 24 hr), Time and Frequency Domain
Author Oliveira et al. (2012b) – Abstract Only
Sport Male, Caliber Unknown, Soccer (n=10
Aim The aim of this study was to analyze whether the heart rate variability (HRV), assessed at the beginning of a soccer preseason, reveals a correlation with the improvement of physical performance over this training period.
Main Findings There were significant improvements in Yo-Yo IR1 performance & in the 30-m sprint time. The qualitative analysis revealed that the differences in Yo-Yo IR1 performance were very likely positive, were almost certainly positive for the sprint, but were inconclusive for the vertical jump. There was a strong correlation between one parasympathetic index and the change in performance. The study showed a strong correlation between parasympathetic indices of HRV with the performance improvement in Yo-Yo IR1 in the athletes during pre-season.
HRV Analysis Non-daily, Unknown
Author Rodas, G. et al. (2011) – Abstract Only
Sport Elite, Field Hockey (n=? entire team)
Aim To determine the changes in HRV during the 2006 World Cup
Main Findings HRV decreases progressively & the values of the parameters related to parasympathetic system activity (RMSSD & HF) reduce, which are indicative of good psychic-physical adaptability to the workload. At the same time, the value of the parameters related to sympathetic system activity (LF and LF/HF) increases, suggesting an increase in fatigue, tiredness and poor adaptability in general. Consequently, the analysis of HRV may be a good marker for monitoring the psychic-physical state, cardiovascular adaptability during exercise & a possible state of physical overload in athletes participating in competitions.
HRV Analysis Day of competitions only – Time and Frequency Domain
Author Martin-Sanchez et al. (2011)
Sport Male Pro Soccer (n=12) & Age/Sex matched Amateur Soccer (n=9)
Aim To determine if an intensive preseason training program modifies the inflammatory status in professional soccer players and if this inflammatory profile may be associated with the physical state.
Main Findings A negative association between cardiac low frequency & the plasma content of alpha-1 antichymotrypsin isotype 4, & a positive association between cardiac low frequency & fibrinogen gamma-chain isotype 3 was found. Our results suggest that the cardiac functional state of soccer players may be correlated with these proteins. Pro soccer players showed a decreased content of circulating proteins associated with inflammation compared with those in recreational soccer players.
HRV Analysis Morning of analysis – Time and Frequency Domain
Author Cipryan et al. (2010)
Sport Male, Hockey Junior Level (n=8), Adult (N=10)
Aim To present inter-individual differences in the reaction of autonomic nervous system (ANS) activity to the same training program, and to thereby support the importance of individual training in team sports during the conditioning period.
Main Findings The SA HRV monitoring mostly revealed significant differences in the level of the ANS activity among the players. A number of junior & adult players were characterized by almost permanently high ANS activity whereas other players occurred below the ANS activity level of healthy individuals.  The training efficiency (overreaching and injury reduction) can be positively influenced by creating training groups of players with similar ANS activity.
HRV Analysis Non-daily – Frequency Domain
Author Cipryan et al. (2007)
Sport Male, U-18 National Level Hockey (n=4)
Aim To investigate the influence of regular sport training on the activity of the autonomicnervous system (ANS) and to disclose patterns of interrelations between them.
Main Findings The results demonstrated that the player with the highest average TS (total score)& the highest average PT(total power) also showed the most consistent results & objectively the best performance in sport. On the other hand, the player with the lowest average TS and the lowest average PT also obtained the lowest average mark in the coach’s evaluation of his sports performance. The tendency to progression of the ANS  activity was different for each subject. The self-reports health status survey, which was given before measurements were taken, did not correspond with the results of the SA HRV measurement.
HRV Analysis Non-daily, Frequency Domain
Author Hap et al. (2010)
Sport Male, High Level Volleyball (n=8)
Aim The goal of the work was to verify the possibility of volleyball playersʼ training load optimization during a one week training microcycle based on the longitudinal observation of dynamics of SA HRV complex indices.
Main Findings 2 Players had above average levels ANS activity indicating higher training loads could be tolerated.4 Players had low ANS activity (but not below average) showing evidence of some fatigue and adaptation. Training loads are appropriate.

2 Players had below average ANS activity and their training adaptability was reduced.

HRV Analysis Daily – Frequency Domain
Author Parrado et al. (2010) – Abstract Only
Sport Elite, Field Hockey (n=? entire team)
Aim The aim of the study was to examine the utility of perceived tiredness to predict cardiac autonomic response to overload among feld hockey players during the 2006 World Cup.
Main Findings Results showed a negative correlation between perceived tiredness scores & time domain indexes, & a positive correlation of perceived tiredness scores and the high frequency component ratio (LF/HF ratio) of heart rate variability. Anxiety did not influence the precompetitive cardiac response despite somatic anxiety’s correlation with sympathetic response (LF/HF ratio) & tiredness scores. Perceived tiredness predicted the autonomic cardiac response to competitive overload. Thus, the perceived tiredness assessment would be a good early marker of fatigue & overload states during competition
HRV Analysis Day of analysis, Frequency Domain
Author Mazon et al. (2011)
Sport Male, Volleyball (n=32)
Aim To investigate the effects of selective loads of periodization model (SLPM) on autonomic modulation of HRV and endogenous stress markers before and after a competition period in volleyball players.
Main Findings SLPM did not change the cardiac autonomic modulation of HRV, but promoted beneficial adaptations in athletes, including positive changes in the plasma concentration of the endogenous stress markers. The absence of changes in HRV indicates that there is no direct relationship between cardiac autonomic modulation & endogenous stress markers in the present study.
HRV Analysis Pre & Post Training Cycle, Frequency Domain
Author Di Fronso et al. (2012)  – Abstract On
Sport Male, Amateur Basketball (n=7)
Aim To investigate the relationship between Heart Rate Variability (HRV) and performance in players of a basketball team during playoffs.
Main Findings Findings of this study suggest that vagal activity, expressed by HF index of HRV, can be positively related to the athletes’ performance. In particular, higher values of HF index during the morning of the match were associated with higher levels of athletes’ performance during the game.
HRV Analysis Morning of Competitions – Frequency Domain
Author Dranitsin (2008)
Sport Elite Male (n=12) and Female (n=1) Rowers
Aim The aim of this study was to examine the simultaneous effect on HRV of acclimatization to a hot, humid environment and a transition of five time zones in elite junior rowers.
Main Findings Major physiological adaptation of HRV indices in the standing position during acclimatization to a humid, hot environment, with a transition across five time zones, occurs within the first 5 days in elite athletes before returning to baseline. Indices of heart rate variability in the supine position correlate with the length of high-intensity training sessions on the previous day.
HRV Analysis Daily, Time Domain
Author Iellamo et al. (2004)
Sport Elite Male Rowers (n=8)
Aim To test the hypothesis that training-induced variations in T-wave amplitude at higher training loads are paralleled by changes in HR spectral profile.
Main Findings From 50% to 100% of training load, there was a significant decrease in HRV and increase in sympathetic tone. As training reduced to 50% during the World Championships, HRV returned to base line and a return of autonomic indices to previous levels was seen. 
HRV Analysis Non-Daily – Frequency Domain

I’ll discuss my thoughts on the questions I listed above in my next post.

Please share any studies pertaining to HRV usage in a team setting that I may have missed in the comments below or e-mail me andrew_flatt@hotmail.com

I joined twitter recently too @andrew_flatt

References:

Cipryan, L. & Stejskal, P. (2010) Individual training in team sports based on ANS activity assessments. Medicina Sportiva, 14(2):  56-62 Free Full-Text

Cipryan, L., Stejskal, P., Bartakova, O., Botek, M., Cipryanova, H., Jakubec, A., Petr, M., & Řehova, I. (2007)  Autonomic nervous system observation through the use of spectral analysis of heart rate variability in ice hockey players.  Acta Universitatis Palackianae Olomucensis. Gymnica, 37(4): 17-21. Free Full-Text

Di Fronso, S. et al. (2012) Relationship between performance and heart rate variability in amateur basketball players during playoffs. Journal for Sports Sciences & Health, 8 (Suppl 1):S1–S70 45

Dranitsin, O. (2008) The effect on heart rate variability of acclimatization to a humid, hot environment after a transition across five time zones in elite junior rowers. European Journal of Sport Science, 8(5): 251-258 Abstract

Edmonds, RC., Sinclair, WH., and Leicht, AS. (2012) Theeffect of weekly training and a game on heart rate variability in elite youth Rugby League players. Proceedings of the 5th Exercise & Sports Science Australia Conference and 7th Sports Dietitians Australia Update. 5th Exercise & Sports Science Australia Conference and 7th Sports Dietitians Australia Update Research to Practice , 19-21 April 2012, Gold Coast, QLD, Australia , p. 183. Abstract

Hap, P., Stejskal, P. & Jakubec, A. (2010) Volleyball players training intensity monitoring through the use of spectral analysis of HRV during a training microcycle. Acta Universitatis Palackianae Olomucensis. Gymnica, 41(3): 33-38 Free Full-Text

Iellamo, F., Pigozzi, F., Spataro, A., Lucini, D., & Pagani, M. (2004) T-wave and heart rate variability changes to assess training in world class athletes. Medicine & Science in Sports and Exercise, 36(8): 1342-1346. Abstract

Ke-Tien, Y.(2012) Effects of Cardiovascular Endurance Training Periodization on Aerobic performance and Stress Modulation in Rugby Athletes. Life Science Journal, 9(2): 1218-25. Full-Text

Martin-Sanchez, F. (2011) Functional status and inflammation after preseason training program in professional and recreational soccer players: a proteomic approach. Journal of Sports Science & Medicine, 10: 45-51 Free Full-Text

Mazon, J. et al. (2011) Effects of training periodization on cardiac autonomic modulation and endogenous stress markers in volleyball players. Scandinavian Journal of Medicine & Science in Sports, doi: 10.1111/j.1600-0838.2011.01357.x Free Full-Text

Oliveira, RS. et al. (2012a) Seasonal changes in physical performance and HRV in high level futsal players. International Journal of Sports Medicine. DOI: 10.1055/s-0032-1323720 Abstract

Oliveira, RS. et al. (2012b) The correlation between heart rate variability and improvement in soccer player’s physical performance. Brazilian Journal of Kinanthropometry, 14(6) Abstract

Parrado, E.  et al. (2010)Percieved tiredness and HRV in relation to overload during a field hockey world cup. Perceptual and Motor Skills, 110(3): 699-713 Abstract

Rodas, G. et al. (2011) Changes in HRV in field hockey players during the 2006 World Cup. Apunts Medicina de l’Esport, (46): 117-123 Abstract

Vantinnen, T. et al. (2007) Practical experiences from measuring exercise intensity and recovery state with HR monitoring in team sport. Symposium Proceedings 6th IACSS Calgary, Alberta. Full-Text

 

Planning the Recovery

The inclusion of HRV monitoring into my training has caused me to change my perspective a fair bit on the subject. It has also provided me with a lot more questions than answers, but I don’t consider this to be a bad thing. My main interest and focus has always been on how to increase strength. A quick look over at my bookshelf and I can see that I have accumulated a small library on the topic. In pursuit of increasing my own strength I’ve been on an ongoing mission to discover and learn the best training methods and programs that can get me stronger. Today’s post is about the polar opposite of what I’ve been spending years of my life on learning. That is, the opposite of training. HRV monitoring has inspired me to consider not just appropriate planning of training loads, but the planning of recovery and restoration modalities – the opposite of physically stressful training.

First I’d like to assert my current position or philosophy on training; Your workouts are only as effective as the quality of your adaptation to them. This is analogous to the nutritional concept of being not necessarily what you eat, but what your body assimilates or absorbs from what you eat (I believe it was Poliquin who said that). I believe that the more advanced you get with your training, the more this statement applies. To elaborate on this concept, if you’re out-training your body’s ability to favourably respond to the stress, it doesn’t matter how perfect or scientific your program is. This is what makes monitoring something like HRV so invaluable. Understanding complex training methods and being able to apply them is simply one facet of the overall process. The recovery process also requires planning, structure and strategy.

At this point I wish I could tell you how to perfectly strategize and plan your recovery but I simply don’t know the answers. What I do know, and I’m stealing this term from Mladen Jovanovic, is that a complementary approach to training is necessary. Putting a ton of time into devising your next training cycle must involve considerations of recovery processes. This is not to say that that you must actively perform some mode of recovery at all times but rather that it would be wise to consider matching increases in training stress with a logically applied increase in recovery strategies to assist in the recovery and adaptation process.

Below is a brief list of factors I’ve been considering more when planning my training/recovery process;

(Note that the following are simply stated to provoke thought, I’m not recommending anything in particular as I’m not qualified to do so)

Sleep: Quality and length are obviously important during all phases of training. Can Inclusion of daily naps at certain times/phases be of any benefit? What about time of day training? Myllymaki and colleagues (2011) found that late night exercise resulted in higher heart rates during the first few hours of sleep compared to control however no effect on overall sleep quality or nocturnal HRV was seen. Perhaps post exercise static stretching would further reduce HR post-exercise (see below: static stretching) – You can monitor your sleep with mobile apps although I have yet to do this.

Nutrition:

–          Macronutrients, caloric intake (matched to body composition and/or weight class goals), manipulation of macronutrients according to training phase (i.e. higher volumes accompanied with higher carbohydrate intake?)

–          Micronutrition (Ensuring adequate vitamin and mineral consumption. Does this change with variations in training load?)

–          Anecdotally I can say that I almost always see an acute spike in HRV the morning after a night of purposeful overeating.

–          Ingesting foods that are anti-inflammatory? Reducing or eliminating foods that are pro-inflammatory? For a discussion on nutrition and HRV see this post.

Supplements: Inclusion of ergogenic aids at appropriate times; vitamin D over winter; supplemental forms of Zinc, Magnesium, C, etc. Rather than taking certain supplements year round would they be more effective by being cycled in at certain times?

Massage: Beneficial in periods of high loading? Massage has been show to acutely increase HRV in athletes (Arroyo-Morrales 2008) and healthy subjects (Delaney 2002). See Patrick Ward’s site for more insightful discussions on HRV and massage.

Static Stretching: I understand that static stretching is a bit of a hot topic and is widely debated. But static stretching post-workout increases HRV (Mueck-Weymann 2004, Farinatti et al. 2011) and therefore more rapidly initiates the recovery process. How much of an effect this may have on the overall process I cannot say but it’s worth considering.

Cold Water Immersion: The effect this has on recovery is debateable (see a good article by Dr. Marco Cardinale here) but it does appear to enhance parasympathetic reactivation post-exercise in athletes after supra-maximal cycling exercise (Buchheit et al 2009). The psychological effects of this shouldn’t be ignored either. Does it matter if something like this actually helps if the athletes wholeheartedly believe it does? When I played football during my undergrad the cold tubs were a MUST during training camp. None of us questioned this. If we sat in the cold tub we thought we helped our recovery. If we didn’t we would expect to be more sore the next day. Placebo effect?

Active Recovery: From personal experience I’ve seen a noticeable difference in perceived recovery, also reflected in my HRV scores with active recovery work. However, incorporating active recovery at certain periods and removing it from others may enhance its effects.

To reiterate, the above modalities may or may not be the answer to continued progress. However, their strategic planning and application throughout training may allow you to better handle the higher training loads necessary to stimulate further progress. We periodize the amount of stress we apply to our body’s, why not also periodize modalities that theoretically may enhance our ability to tolerate that stress at the appropriate times?

For the strength coaches reading this, I’d be curious to know how much thought and planning goes into this aspect of your training with your athletes. Do you have your athletes use different recovery interventions? When and why? Do you monitor this?

I am still young and relatively inexperienced compared to many of you that may be reading this. I can say that from my experience coaching strength and conditioning at the collegiate level that monitoring can be an extremely arduous task given the limited amount of time available with the athletes. Not to mention, the process of monitoring is time consuming in and of itself, making it difficult to do when you’re responsible for several teams.

Leave me a comment or send me an e-mail to continue the discussion.

andrew_flatt@hotmail.com

References:

Arroyo-Morrales, M. (2008) Effects of myofascial release after high-intensity exercise: A randomized clinical trial. Journal of Manipulative and Physiological Therapeutics, 31(3): 217-223.

Buchheit, M. (2009) Effect of cold water immersion on postexercise parasympathetic reactivation. American Journal of Physiology, 296(2): 421-427 Full-Text

Delaney, J. (2002) The short-term effects of myofascial trigger point massage therapy on cardiac autonomic tone. Journal of Advanced Nursing, 37(4): 364-371

Farinatti, P. et al (2011) Actue effects of stretching exercise on the heart rate variability in subjects with low flexibility levels. Journal of Strength and Conditioning Research, 25(6): 1579-1585

Mueck-Weymann, MG., et al (2004) Stretching increase heart rate variability in healthy athletes complaining about limited muscular flexibility. Clinical Autonomic Research, 14(1): 15-18

Myllymaki, T. et al (2011) Effects of vigorous late-night exercise on sleep quality and cardiac autonomic activity. Journal of Sleep Research, 20(1): 146-153

HRV, Adaptation, Progression, Training Adjustments

I’ve been reviewing my HRV trends over the last few weeks to analyze how my body is handling my current training set-up. I’ve been noticing smaller drops in HRV the day following a heavy workout (sRPE9). In some instances I’ve seen a small hike in HRV the following day. Today I will provide a few thoughts on what may be happening as well as some thoughts on things to consider when analyzing your data.

It’s been demonstrated in the research quite clearly that HRV reflects recovery status in both weight lifters and aerobic athletes. Therefore, it’s reasonably safe to say that your HRV score the morning after a workout is reflecting how stressful the workout was. However, it’s extremely important to consider other variables that can affect recovery (other stressors). So taking this into consideration, HRV score reflects not so much the stress of the workout, but rather how well your body was able to respond to it since the cessation of yesterday’s training session (assuming the workout was the biggest stressor of the day).

Let’s say you performed an intense workout that you rated a 9 out of 10 on an RPE scale. The following day your HRV score will depend on the following key variables;

Nutrition: Did you provide the resources for your body to recover from the session? Proteins for structural repairs of damaged muscle fibers, fats for overall calorie intake and hormonal support and carbohydrates for glycogen re-synthesis. Was overall calorie intake sufficient? 

Purposeful Rest/Relaxation: Following the workout did you start the recovery process by relaxing, hot shower, etc.? This will allow the parasympathetic nervous system to get the recovery process underway.

Compounding stress: In contrast to the above, did you add further stress to your body? How physically active were you? What stressful events occurred and how bad were they?

Sleep: How restful was your sleep? How many hours? Were there disturbances?

Aerobic Fitness/General Physical Preparedness: The more aerobically fit you are, generally the better your HRV will be. The higher your work capacity, the more stress your body can handle. In my experience, in effort to increase performance in a given quality, it’s important to consider the overall fitness of the individual as this can limit and effect recovery, training frequency, volume, intensity, etc.

Familiarity of the Training Session: What type of workout was it? Have you performed this workout recently with similar loads? In other words, has your body adapted to the workout structure which therefore reduces the stress on the body?

I would like to elaborate on the last point since the above are pretty self-explanatory. When considering HRV response to a training session, it’s important to evaluate if you are introducing a new stress to the body via new workout structure, type and familiarity of work (aerobic, anaerobic, running, rowing, resistance, etc.). It’s been my experience that a new workout structure or unfamiliar training will create a larger drop in HRV. This is obviously because your body is not accustomed to the type of work and must work hard to adapt and recover. For example, the first time I performed a conditioning session this past year my HRV dropped immensely. However, each conditioning session thereafter provoked less and less of an HRV drop. HRV reflected my progressive adaptation to the stress. Even though the workouts may still have been perceived as hard, the body is familiar with the stimulus and homeostasis is quickly restored.

Some follow up questions based on the above discussion;

  1. Is the workout still effective if it does not provoke a marginal stress response (drop in HRV)?
  2. Should we use HRV as a guide to adjust and make changes to training structure to avoid staleness/plateau (periodization)?

In addressing question 1, it’s important to first evaluate training progress. Check your workout log. Are you still getting stronger/faster/running further, etc (whatever your training goal is). If the answer is yes, continue. Other factors and adaptations are obviously taking place.

In response to question 2, we need to carefully examine all of the above factors that affect an HRV score. If your nutrition is on point, you are reducing compounding stress, sleeping well and so forth, we can assume that the following day’s HRV is a reflection of your response to the training session.

If you’re experiencing a plateau it’s time to consider altering training. If you are a strength athlete you have a few options. Adjust volume or intensity. Adjust training sequence/frequency. Make adjustments to the lifts themselves. For example, add a pause to your bench or take it away, rotate assistance lifts, add or remove an exercise. Obviously only one major adjustment is needed. Evaluate progress, keep track of HRV trends and see if that made a difference. It’s also important to consider that training progress in more advanced athletes/lifters is non-linear. Therefore, don’t make drastic changes at the first sign of plateau. It’s okay to repeat workouts. Use your judgement on if a change is needed.

I will continue with my current training structure and set up to see if progress continues or stops and if HRV trends change or stay the same. Once I can evaluate more of my data I’ll write up a report.

Managing Training for Strength

In my last post I discussed some of the shortcomings of pre-planned training. This inspired a conversation between myself and a friend about percentage based training. Today I’d like to talk about some thoughts I have on this topic. Additionally, I will offer some potentially better strategies to help manage and adapt your training on a day to day basis.

To be clear, percentage based training (in the context of this discussion) refers to planning training loads based on a percentage of your 1 rep max in a given lift.

For example, if your 1 rep max in the Bench Press is 300, you know that 50% of this is 150. Strength is generally believed to best be built by working over 85% of your 1 rep max. From our example, 300x.85=255 and therefore 255 is 85% of our 1 rep max of 300. The purpose of using percentages is to control the level of intensity, effort and fatigue placed on the body to create a desired effect. Generally, you can perform only 1 rep with 100%, 2 reps with 95%, 3 reps with 90% and so on.

% 1RM

100

95

90

85

Reps

1

2

3

5

I think that percentage based training is most effective for novice to intermediate level lifters. This is because they are nowhere near their strength potential. Progressing from workout to workout is much more feasible for them. They can adapt better and faster to the loads because the loads simply aren’t that great yet.

Now for a more advanced trainee, percentage based programs can be less beneficial for several reasons.

  • Percentages are based off a 1rm (or a calculation of a 2-5rm) that were taken on a given day. Your strength levels can and will vary day to day based on recovery status, stress levels, nutrition and several other factors. Therefore a percentage based off the 1rm recorded on a previous day will unlikely be a true reflection of present strength levels.
    90% of your 1rm can easily be 100% on an off day. We’ve all had workouts where the weights felt heavy. We’ve also had days where the weights felt light. If you grinded out 85% for 3 hard, sloppy reps, was it really 85%? In reality it was more like 90%. This can create problems in the program because 85% x3 should generally be a very manageable lift and therefore not tax the body too much. However, since the weight was actually much heavier than 85% on that given day, we’ve created more stress and fatigue then was called for. This is how we set ourselves up for missing lifts in subsequent workouts and nothing is more frustrating than missing lifts.
  • Pre-planned percentage based training is basically telling your body that it must adapt to the training rather than allowing your training to adapt to you. Unfortunately, we do not have conscious control over how we adapt or when. Therefore, it would be much wiser to plan according to the current strength and adaptability levels of our body. We can’t force our body to get stronger.. often times when we try and do this our body tells us to suck it and we regress, or worse, we get hurt. I’ve been down that road.

How do we adapt our training to our body?

1.

I’ve become a big advocate of using RPE (ratings of perceived exertion) to manage training loads. I first learned about RPE when studying for the CSCS exam several years ago. However, it wasn’t until I read Mike Tuchscherer’s Reactive Training Systems Manual that I really started to incorporate them into my training. Essentially, with an RPE system we plan to work up to a given RPE for a given amount of reps and sets as opposed to using a percentage of a 1rm. This allows us to “pre-plan” our training in accordance with our most current strength level. The following chart shows how a RPE score corresponds to effort level.

RPE

Reps left in the tank

10

0

9

1

8

2

10 is an all out effort. It can be a 1 rep max, a 5 rep max or any number really. As long as it was an all out effort where you are unable to perform another rep. An RPE of 9 means you had 1 rep left in the tank. There is a huge difference between an RPE of 9 and 10 due to its effect on the CNS. It takes much longer to recover from a 10 than a 9. This is what makes RPE’s more accurate than percentages.

This system eliminates missed reps at a given percentage because the selected weight is now much more accurate and fits your present strength levels for that day. For more info on RPE’s check out Mike’s book and free articles on his site.

2.

Pay attention to indicators. Things such as sleep, stress, nutrition and restoration work can all have a pretty drastic effect on your strength levels and adaptability. The following is a list of different indicators you can start to monitor if you don’t already.

  • Sleep: I rate my sleep on a scale of 1-5.
    5 = 7-8 hours of sleep, no wakes or disturbances, morning wood, etc
    4= 1 disturbance or wake up during the night
    3= less than 7 hours of sleep, and/or multiple wake ups
    2=Usually if I’m sick and can’t fall asleep
    1=no sleep
    Supplementing with ZMA really helps improve the quality of my sleep.
  • Stress: Primarily for this I use HRV measurements. I’m not going to elaborate on this since I’ve written about it extensively in previous posts. If you’re unfamiliar with HRV then I highly recommend you click here and start with “HRV Explained Part 1″.

    If HRV isn’t an option for you there are other way’s to monitor your stress. I have to thank Simon Wegerif (creator of iThlete) for introducing me to this method in a conversation we had over Skype. Stress can be classified as; physical, mental or chemical.

    Physical Stress = training, labour, etc.

    Mental Stress = financial problems, fighting with a significant other or parent, travel, death in the family, etc.

    Chemical Stress = Alcohol intake, poor or inadequate nutrition, etc.

    You may not perceive things like poor nutrition or mental stressors as significant stress, but I assure you, they play a big role in how strong you’ll be on a given day and how much further training stress you can handle.

    Rate each one of these on a scale of 1-5. You’d be surprised what you discover by monitoring stress and how it relates to and effects your strength levels

    I love the HRV app because it plots your stress levels on a chart so you can see trends over time. Looking back over the trends with your training log and indicators tell you a lot about what’s working and what’s not.

  • Restoration Work: Foam rolling, stretching and moderate aerobic work can have a huge impact on your recovery and fitness levels. I will reserve writing about the benefits of aerobic work for strength athletes now since I plan to write an entire post on it in the future, but understand that a little cardio (in the form of jogging, sled dragging, etc) goes a long way in contributing (indirectly) to strength gains. I simply keep a log of what type of aerobic work I do, for how long and if I use a sled I track the weight.
  • CNS Test: Finally, I like to perform a quick CNS test after my warm-ups but before I start lifting. This can be in the form of a vertical jump, broad jump, grip test or whatever else you can think of. It’s important to be consistent. Compare your daily result to your baseline or average and that will usually indicate how your workout will go. I’ve actually found that skipping (yes, jumping rope) is a good indicator for me. Some days I can skip like a 3rd grade school girl with flawless technique. Other days I can’t get into a rhythm and stomp the rope every ten jumps. I’ve found that this has a correlation to my strength performance that day.

The longer you train and more advanced you get, the harder it is to make progress. If you haven’t adopted any of the above strategies to help monitor your training I encourage you to consider some. You have nothing to lose and only strength to gain.

Thanks for reading.