Training Load and Nutrition Impact on HRV: 10 Week Data Analysis

Below is 10 weeks worth of my own training data that includes;

  • HRV – Collected daily on ithlete in standing position immediately after waking
  • HR  – Taken from the ithlete HRV measures
  • Load – Sets*Reps*Weight(lbs)
  • sRPE – Reps*RPE of session(1-10 scale)

All data is presented as weekly mean values.

HRV & Load

HRV & Load

HRV & sRPE

HRV & sRPEHR & LoadHR & Load

HR & sRPE

HR & sRPE

Data

Data

Training

– Training volume in weeks 1-5  involved 3 straight working sets for main lifts alternating between weeks of 5’s, triples and singles. Working weight for each set was predetermined based on previous week but would be adjusted if need be. Training volume progressively decreases as working sets were reduced from 3 top sets to 1 top set. Assistance work was mostly just maintained during the reduced load period. Week 10 was more of a  true deload where all working set weights were reduced but only to about 80% while assistance work was reduced slightly as well. Keep in mind that volume for each week would vary based on whether I was performing sets of 5, 3,  or 1 for top sets.

Thoughts

– Even prior to week 1 displayed in the data, I had not taken a deload in quite some time (end of August). Performance (strength) had progressively been increasing and I didn’t feel the need so I kept at it.  My HRV was consistently averaging in the low 70’s which is quite low compared to my typical average of  about 80 (based on several years of data).  Once I started having some nagging soft tissue problems accumulate I decided to taper the volume.  I was seeing how my body and HRV responded to deloading keeping intensity high but just cutting volume. HRV trended back towards baseline though soft tissue problems weren’t quite resolved.

– Week 10 was Thanksgiving week and I traveled to my folks place. Training was reduced yet HRV decreased. I attribute this entirely to the drastic change in my nutrition during this week. Fruit and Vegetable intake decreased significantly. Processed foods and carb intake increased dramatically. It was an atrocious but delicious week of eating. This is not the first time that I’ve seen HRV change due to similar changes in eating.

– In the chart below you can see HRV decline during the high volume/load period followed by a progressive increase during the taper. This is then disrupted with a progressive drop during Thanksgiving week of binge eating. HRV then trends back up this week as eating improves and regular training resumes.

Trend 9 to 12_2013

– HRV and HR need to be taken into context when being used to guide or monitor training. Other stressors always need to be considered. Neither will ever perfectly correlate with training load as this would assume that only training affects the ANS. It also worth mentioning that HR reflected training load better than HRV in this case and simple RHR should certainly not be dismissed or overlooked.

– Acute changes in HRV/HR won’t always “make sense” or correspond to perceptions of soreness, fatigue, mood etc. (though they do quite often). The weekly mean values tend to provide a better reflection of training/life style. I don’t adjust training on a day to day basis basis until I’m approaching my top sets.

HRV and Training Density

I’m about to start week 3 of a new training cycle. In reviewing my HRV trend from the past two weeks you’ll see a massive change from week 1 to week 2. Clearly, last week was significantly more stressful than week 1. This was unintentional. I decided to do some calculations to see what may have happened.

1 Month Trend

1 Month Trend

The goal of this phase is to progressively accumulate volume with moderate loads over a 3 week period with a slight reduction in week 4. However, I am very undisciplined in these phases and always go heavier than I should, too soon. I vary set/rep ranges each week but try and stick to lower RPE’s. I like to really focus on technique development during these phases since the loads are supposed to be lighter.

Here is what the two weeks looked like for my main working sets (assistance work not included as it was very similar):

Week # of Lifts Total Volume Avg. RPE
1 70 43300 7-8
2 56 43200 8-9

Total volume was pretty much unchanged but should’ve increased slightly. RPE generally went up to 9’s on my last set in each workout of week 2 (straight sets) but should’ve remained at 8 or below (no chance I was taking weight off the bar though -my meathead-self trumps my logical-self in the gym quite often). Number of lifts decreased by 20% yet volume was matched due to a relative increase in intensity; too much, too soon. If my goal was to increase training density, than I would’ve been quite successful.

I selected weight ranges in week 2 that should’ve been at the appropriate RPE based on estimations. However, for whatever reason, starting on Monday the weight didn’t feel as light as it should have. Rather than lower the load like I should have, I simply performed less sets.

Regarding HRV, I do expect to see some progressive decline as volume increases,  but not a -8 weekly change. Though I can’t think of anything major outside of training that could’ve contributed to the significant change in the trend, non-training related stressors are always a factor, whether we perceive them to be or not.

In conclusion I failed to accomplish my goal of progressively increasing volume with moderate loads but rather increased training density purely as a result of undisciplined load selection. HRV responded with a significant decrease in the trend and I am now starting week 3 in the hole. Lesson learned.

HRV and Reaction Test Data and some updates on our HRV research

I posted some data a couple of months ago comparing my HRV to my tap test results to see if there was any correlation between the two. You can see that post here if you missed it. It was around that time that I also started using a Reaction Test app. Today I’ll be posting and reviewing my Reaction Test data with my HRV data to see what it might reveal. At the end of the post I’ll provide some brief updates on what’s been happening since I started working in the Human Performance Lab here at Auburn (Montgomery).

HRV: I continue to use ithlete as my main HRV metric. Daily measurements are performed each morning after waking and bladder emptying. All measurements are performed in the standing position with paced breathing. The HRV value provided by ithlete is Ln RMSSD x 20; a time domain measure of parasympathetic tone.

Reaction Test: The reaction test is performed after my HRV test and my Tap test (I’m still doing these but will not include them today). All reaction tests were performed using right index finger. The app functions as follows;

  1. initiate app
  2. Tap target area to start the test
  3. React to stimuli (color change) as fast as possible by tapping the screen
  4. Repeat for a total of 5 reactions (variable time intervals between)

Image

I used excel to calculate daily average with the reaction test data (plotted on the charts below).

Keep in mind that for a correlation between high HRV and good Reaction Test, we want to see an inverse relationship in the trends. We’re looking for a fast Reaction time (trending down) with a higher HRV score (trending up).

Chart 1 – HRV, Reaction Test Average and Session RPE (secondary axis)  

Image

For more clarity I’ve also included excel screen shots of the raw data. I’ve sectioned off 4 different areas and noted the goal/purpose of that particular time of training. It works out so that there is a High Intensity section, a Deload section, a High Volume Section, and a Semi-Deload section. The “Semi-Deload” period occurs over the past week that I’ve moved to Alabama. I figured it would be wise to scale intensity and volume back very slightly while I settle in to a new place and new work environment. To give an example, I essentially removed a main working set and stuck with familiar weights. Assistance work was relatively unchanged.

ImageImage

* I must have forgotten to perform a reaction test or forgot to save it on 03/16 which was a Saturday and therefore it is not included.

I’ve highlighted any score that was +/- 10% from the total average. So for exampme; if HRV was 10% higher than the average of all HRV scores, I would shade that day green. Likewise for Reaction Test. Red shading denotes 10% or greater reduction.

After examining the acute relationship between Reaction Test and HRV I decided to examine the averages for each training block. I’ve shifted my focus lately a little bit more on weekly trend changes vs. daily trend changes. As you can see in the charts below, there is a very strong relationship between HRV AVG and Reaction Test AVG during each training section.

ImageImage

–          Intensity Section – This section was the last 2 weeks of my 9 week training cycle that I performed after the Christmas break (discussed here). Volume was low but intensity was Maximal. HRV is at it’s lowest average while Reaction Test is at its highest (slowest reaction time) average.

–          Deload – During the deload week HRV average rebounds to peak levels while reaction time improves to near peak levels.

–          High Volume – This marks the start of a new training cycle. HRV drops quite a bit and Reaction Time average increases (slower reaction).

–          Semi-Deload – HRV returns to near peak values while Reaction Test peaks (quickest reaction time average).

From this data set, intensity appeared to have the biggest effect on Reaction Test average and HRV average. High volume work with moderate intensity also had a significant impact on these averages. It should be kept in mind that the Intensity period followed several weeks of training and therefore some fatigue had already been accumulated. I didn’t start using the reaction test until late February.  HRV and Reaction averages improve over periods of reduced training load.

Given that I was able to hit some PR’s in the gym during the Intensity section (under high fatigue), I’m inclined to say at this point, based on this data set, that these tests are not necessarily indicators of performance potential (strength), but rather markers of fatigue. In the future I would like to see how these tests match up with “finer” motor skills in other athletes.

Quick Updates

I made it safely to Montgomery, AL after a nice visit with some family at my folks place in Cincinnati over Easter. Total travel time was about 17.5 hours. We wasted no time in getting to work in the lab. We’ve got 3 projects going on right now (the first two being more health related  as opposed to sports/performance).

  1. I’m helping Dr. Esco complete a study comparing post-exercise HRV recovery after two different modes of exercise (cycling vs. treadmill at same intensity/duration).
  2. We are starting a new study comparing post-exercise HRV in middle aged men after 3 modes or resistance training; Eccentric only; Concentric Only; Traditional Resistance Training
  3. We have put the wheels in motion for a cross-validation study comparing ithlete to EKG. We did some pilot work with about 6 subjects so far and have IRB Forms and Consent Forms about ready for submission. We’ll measure ithlete and EKG simultaneously in about 20 males and 20 females then run the data. This is a very important study to me. In order to improve what we know about HRV and performance, we need more data. Using EKG’s in the field is not practical. What we need to start seeing is data from athletes that are performing measurements at home when they wake up. The device needs to be extremely easy to use and the data needs to be immediately available to the coach. At this time, smart phone app’s are the best way to do this. There are plenty of limitations with this but at the end of the day, if we’re going to apply this stuff in a team setting we need easy to use, affordable tools.
  4. This last project doesn’t exist yet. But I’m hoping to collect data on either the men’s tennis team or the women’s soccer team. I’ll provide more info on this if and when it starts to take shape.

Let me be clear right from the start in saying that Dr. Esco is running the show here. I’ve learned a ton from him already about the research process and anything that I accomplish over the next little while will be because of him.

Lastly, I attended my first Roller Derby which was quite the experience.

HRV and Deload Periods

Before I review my own data from my overload and deload period, I first wanted to discuss some of the available research that I have pertaining to HRV response to overload training and following recovery.

Some Research Pertaining to HRV and Taper/Deload Periods

Pichot et al. (2000) monitored HRV in middle distance runners over 3 weeks of intensive training followed by a 1 week recovery week consisting primarily of moderate aerobic work. RMSSD decreased progressively over weeks 1-3 and rebounded to peak values during the recovery week.

Pichot et al. (2002) found that RMSSD increased after an aerobic training period in sedentary subjects. After transitioning to a 4 week overload period, RMSSD decreased significantly followed by an abrupt rebound reaching peak values during a 2 week recovery period.

In a study by Baumert et al. (2006), baseline HRV values were established prior to training camp in track and field athletes. After week 1 of a 2 week training camp, RMSSD declined significantly. At 3-4 day’s post-training camp, RMSSD started to return toward pre-camp basal values.

In elite rowers, Iellamo et al (2004) reported that HRV indices decreased as training load increased from 50% to 100%. However, during a taper for the World Championships, HRV values returned to baseline. “Reduction in training load during the World Championship resulted in a return of autonomic indices to the level observed at 50% training load”

Though not a comparison for pre and post HRV values following overload, Buchheit et al. (2004) showed that moderate training loads are better than no training or intensive training for the purposes of increasing vagal-related HRV indexes. Their data revealed that moderately trained individuals had higher basal HRV values compared to sedentary and highly trained individuals.

Reviewing my data

In older posts I discussed my experimentation with not taking planned deload weeks but rather reducing training loads on days when HRV was low. This method of managing training loads worked very well during times of consistent, albeit, relatively unchanging training. However, due to work/travel schedules and other set-backs I really didn’t plan any overload training. I was mostly doing my best at not losing strength. A feat much easier to accomplish than gaining strength. At the present time, I believe that one can get away without doing week long deloads at fixed intervals (every 4th week or so) if training is managed on a daily basis. However, by design, this set-up really doesn’t allow for overreaching as you would back off as soon as your trend declined for too long. 

It was my goal in my latest training cycle to not focus on daily HRV changes but instead evaluate weekly changes. My training, though still manipulated slightly on a day to day basis (particularly in week 4 of the cycle) was much more pre-planned than I had been doing previously. My training set-up was designed so that HRV would return to above baseline after each weekend.. which it did. The purpose of this was to be fresh for the beginning of each week and to avoid premature overreaching. A deload was planned following the last week of the cycle. 

Below is a screen shot of my HRV trend that includes interesting trend changes in response to different events/training. See my previous post here for a more extensive review of my 9 week training cycle. This post will focus primarily on the last 3 weeks of the trend (weeks 8, 9 and 10 of the cycle)

deloadtrendmarch2013

During week 6 and 7 of my trend HRV baseline reached peak values since the holidays. However, during weeks 8-9 HRV steadily decreases. In fact, in week 9, HRV remains below baseline until the weekend. Typically my HRV will come back up after a recovery day on Wednesdays. The difference between weeks 6-7, 8-9, and 10 are volume and intensity related.

During weeks 6-7 my training volume reduced and my intensity increased only slightly. In week 6, it is reasonable to say that I reduced more stress than I added based on volume and intensity change and sRPE. In week 7 however, there are 2 sRPEs of 9 which marks the initial decent in the trend. During weeks 8-9, volume reduced only slightly but intensity increased to near maximal in week 8 and as close to maximal as I could get in week 9. In that 14 day period I performed 8 workouts of near maximal or at maximal intensity on my main barbell lifts.

It was also during these last two weeks of the training cycle that I experienced nagging pains, high levels of soreness etc.

Though weeks 8 and 9 are the most taxing, my sRPE doesn’t change all that much (primarily 8’s with a rare 9). This does not do a good job of reflecting the change in volume/intensity. Perhaps I need to re-evaluate my current method of rating workouts and tracking training load.

Week 10 is a deload week and HRV returns to peak levels. Soft tissue problems progressively resolve and I’m anxious to start a new cycle.

Wrap Up

HRV will likely decline during intensive training and return to baseline following a recovery period of reduced training loads. Perhaps focusing more on weekly changes in HRV as opposed to daily acute changes is more meaningful during overload periods; permitting a more controllable approach to overreaching.

References

Baumert, M. et al. (2006) Changes in heart rate variability of athletes during a training camp. Biomed Tech, 51(4): 201-4.

Buchheit, M., et al. (2004) Effects of increased training load on vagal-related indexes of heart rate variability: a novel sleep approach. American Journal of Physiology – Heart & Circulatory Physiology, doi:10.1152/ajpheart.00490.2004.

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.

Pichot, V., Busso, T., Roche, F., Gartet, M., Costes, F., Duverney, D., Lacour, J., & Barthelemy, J. (2002) Autonomic adaptations to intensive overload training periods: a laboratory study. Medicine & Science in Sports & Exercise, 34(10), 1660-1666.

Pichot, V., et al. (2000) Relation between heart rate variability and training load in middle-distance runners. Medicine & Science in Sport & Exercise, 32(10): 1729-36.

Reviewing HRV data after a 9 week training cycle

It’s been a quite a while since I can honestly say that I completed a successful training cycle with little interruption. After Christmas break I had a 9 week cycle tentatively planned out. As you’ll see, the plan changes due to unforeseen events, but training manipulations were made and the cycle was successful; resulting in some gym PR’s  which haven’t been made in a long time!

Set up was as follows;

Monday – Squat

Tuesday – Bench

Wednesday – Active Recovery (20-30 mins of light aerobic work, mobility, stretching, etc.)

Thursday – Deadlift

Friday – Incline Bench

Saturday – Off or Active Recovery

Sunday – Off

Weeks 1-4 were of moderate intensity (75-85%) and higher volume. An example of a typical workout from this phase would be 5×5, 6×4, etc. However on deadlift day’s I’d rarely perform sets with more than 3 reps. Weights were selected based on RPE and guided by previous session’s working sets. If you look at my trend closely however, you’ll see that week 4 was a lousy week and my workouts were adjusted accordingly (more below).

Weeks 5-7 were of higher intensity (85-90%) and moderate volume such as 3×4, 4×3, etc.

Week 8 consisted of 1-2 sets of 2 reps with a weight that was near but not quite maximal

Week 9 was test week where I worked up to as close to a 1RM as I could get safely (I train alone).

Essentially I was blocking my training up into an “accumulation” period, a “transmutation” period and a “realization” period. I use those terms loosely however.

Below is a screen shot of my HRV/sRPE trend from the last 3 months. The training cycle began on Jan. 7. This is following a period of detraining over the holidays that you can clearly see early in the trend.

JantoMarchtrend2013

Week 1 – Post-Christmas holidays and I’m detrained. I began lifting 3 day’s/week to let my body get back into the swing of training with plans of moving to 4/days week in week 3. Though the workouts aren’t very intense, I experience large drops in HRV in response to workouts. My body is clearly adapting to the re-initiation of training.

Week 2 – My body appears to have adapted well as I experience very few low HRV days. HRV peaks on the weekend after some rest.

Week 3 –Switch to 4/day week lifting schedule. I was surprised that I didn’t see some lower drops this week. HRV peaks again on the weekend after rest.

Week 4 – I miss a workout due to snow day. My HRV is low practically all week and the weights were feeling heavy. I decided not to push it and essentially deloaded with sRPE’s of 7. Below is a screen shot of my data as it appears when I export it to excel from ithlete from weeks 2-4.

*Regarding the comments section, I document some random stuff sometimes. This is simply because I plan to review that data at a later date to see if I notice any trends. For example I note when I have ZMA before bed to see how it effects sleep score and next morning HRV. I’ll try and make note of any changes in nutrition, etc. Since I keep a training log I only document brief details about workouts on ithlete. Keep in mind that the comments , Sleep score and sRPE are all referring to the PREVIOUS day/night. So for example, when you see an sRPE of 8, it was from the workout on the day before. Lastly, I work days/evenings working with athletes so I typically stay up a bit late and therefore wake up later in the morning.

CommentJan2013

Weeks 5-7 run smooth. Training goes well and HRV responds well as my trend actually increases a bit. HRV reaches its lowest point on a Saturday morning at the end of week 7. This was after a long day of work, a workout and a football skills practice I helped coach. This practice beat the hell out of me as I was shouting the whole time so that my kids could hear me over all of the other groups. I was exhausted at the end of the day so I expected a low score the next day.

Weeks 8-9 both go well. HRV drops much lower than I had expected in response to the higher intensities. In the past, heavy workouts with low volume typically don’t create such marked drops. In week 9, my final week with 1RM attempts, HRV doesn’t even come above baseline. I’m also feeling beat up at this point with a sore left pec, tight lateral hamstring on my right side and overall wear and tear. HRV peaks again every weekend after rest.

Week 10 is a deload week and you can see at the very end of the trend that HRV starts to climb back up.

Marchcomments

In my comments above from ithlete you can see when and where certain body parts start nagging, etc. It’s worth mentioning again (as I’ve mentioned this in previous posts), any time I spend time with my family (particularly my nieces and nephews) that I don’t see too often, my HRV is always high the next day.

The results of the training cycle – (all raw, vid’s of some of these in last post and on youtube page)

Squat – 540

–          11lbs shy of my Competition PR of 551 from back in 2010. I’m pretty confident I could’ve hit this if I had a spotter. I made this lift in a relatively relaxed state. Not a true 1RM.

Narrow Grip Floor Press with Pause – 385

–          Due to left pec soreness I decided to test with a narrow grip floor press instead of bench press. This was probably a stupid idea. I’m glad I didn’t hurt it even more. This was a floor press PR. Pec’s already feeling better now.

Deadlift – 565

–          This went up pretty easy. I opted to not go heavier because I’ve had back issues in the past as I’ve discussed several times in previous posts. I did not want to push it just in case. Again, not a true PR (which is 600), but it’s been a while since I’ve deadlifted this heavy due to injury.

Incline Bench – 350

–          I was pretty happy with this since I don’t always include this lift in my training.

My bodyweight throughout this cycle was around 235lb.

I’m moving to Alabama real soon to get started on some HRV research at Auburn. I expect that this will affect my training. I’m hopeful however that the move will be a smooth transition and that I can continue on without too much issue. Unlikely though.

Making HRV More Practical For Athletes: Measurement Frequency?

Perhaps the biggest limitation with HRV monitoring in a team setting is obtaining and maintaining compliance from athletes. Daily HRV measurements can become monotonous, particularly for athletes who may not fully understand the value of the data. One question I’ve had in mind for a while now is; what is the minimal frequency of HRV measurements we can acquire that can still offer meaningful information regarding training status in athletes?

If you’ve read any of the research on HRV and athletes, you’d note that HRV is rarely measured daily. This is likely because having each subject report to the lab everyday to have their HRV measured on an ECG is impractical. However, with the advent of valid and reliable devices such as the Polar RS800, R-R intervals can be collected in the field making more frequent measurements a little more practical in the research setting. However, for the practitioner in the field, an even more practical, economical and user friendly device is desired. Thankfully smart phone app’s such as ithlete were created to accommodate this.

So now we have very affordable, very user friendly smart phone applications that can provide us with HRV data. The trick is getting the athletes to use them often enough so that we can use the data for monitoring purposes. Is it more of a reasonable expectation of our athletes to collect only one or two HRV measurements per week as opposed to every day? Will this provide us with enough information to draw meaningful interpretations from?

After giving it some thought, I decided to review some data over a 3 month period. With my own HRV data, I recreated trends in excel with; once per week, twice per week and daily measurements. The purpose of this is to see what these varying frequencies of measurement reveal in the trend. I’ve also included sleep score data which is graded 1-5 based on perceived quality and quantity after waking.

Daily Measurement 3 Month Trend

 daily3monthtrend

 

–          There is a period of time between the 4th week of December to the 2nd week of January that my HRV trend declines and I rarely see scores over 80. During this time (the Christmas Holidays)I was not lifting regularly and experienced some detraining.

–          Daily measurements allow for sRPE to be recorded providing the coach with a good indication of how the athlete is perceiving and responding to the workouts. Conversely, the sRPE allows the coach to see when the athlete is experiencing high stress in the absence of a high load training day.

–          Daily measurements allow the coach to see acute changes in HRV which can be important in planning or manipulating training.

–          It’s worth mentioning that my highest levels of strength were displayed over the last week of February and early March (early March not included). This is expected as I am nearing the end of my training cycle which has transitioned from moderate intensity/high volume to high intensity/low volume. Coincidentally, my HRV is reaching peak heights. I’m not entirely sure what to attribute these high scores to as I have been doing less aerobic work than normal. This may or may not have any meaning. Some vid’s are posted below from this “realization” phase. 

 

 

 Once Per Week HRV Measurement 3 Month Trend

 onceweekhrv

–          I chose Monday as the reference day because it is the day of the week furthest from training stress that can influence HRV. My goal was to find a day that gives me the best indication of baseline HRV. Since I train Mon-Fri and rest on weekends this left Sunday or Monday as the best options. I selected Monday over Sunday because Saturday nights can be social, late, etc. and therefore affect Sunday morning results.

–          This trend clearly shows my detraining period over the holidays.

–          Given that I adjust my training when necessary to avoid excessive fatigue accumulation, my baseline HRV is relatively consistent apart from the detraining period. Training is being well tolerated because I’m intentionally adjusting my training for that purpose. However, in a more pre-planned setting such as a collegiate weight room the result/trend would likely differ; particularly in a preparation phase (pre-season, early off-season, etc)

–          Coaches should be cautious when using weekly measurements due to potentially low scores caused by non training related stressors that may obscure interpretation. For example, if an athlete has a rough sleep Sunday night, HRV may be lower than usual Monday morning. This does not mean the athlete is fatigued or should have training loads reduced. Therefore, coaches need to keep tabs on performance and feedback from the comments section.  Clearly, weekly measurements have its limitations however it still may offer some value.

Twice Per Week HRV Measurements 3 Month Trend

twiceweek3monthhrv

–          I chose Monday and Saturday as my reference days because Monday represents HRV at rest while Saturday represents HRV after fatigue has been accumulated all week from training. This may provide some insight as to how stressful the training was based on Mon-Fri change in HRV. I am a bad example for this as I try and allow for HRV to reach baseline at least once during the week using Wednesday as an active recovery day. Data from an athlete involved in training, practices, class, etc. would have a different trend.

–          This trend allows for comparison of Sleep quality pre and post microcycle. In my trend, Mondays sleep scores never fall below 4 while there are 2’s and a 3 from Friday night’s sleep.

– As with the weekly measurement, this trend fails to capture major acute changes (highs and low’s).

Final Thoughts

Weekly measurements performed after a day or two of rest to allow for a true measure of baseline HRV can be useful in determining how an individual is coping with training on a week to week basis. However, I would urge you to be very cautious when interpreting trends as a low score caused by poor sleep or something other than training fatigue can provide a false sense of training response. This is where subjective measures, performance indications and regular communication is important.

Twice per week measurements might be the frequency which provides us with the most meaningful information from the least amount of data and therefore demand from the athlete. Seeing how HRV changes from pre to post training over a one week period likely provides much more meaningful information about training status verses weekly measures. It goes without saying that this needs to be manipulated according to the team’s training/practice/competition schedule. I used myself as the example today but most teams will not have Saturday and Sunday completely off from training.

Perhaps starting with weekly or twice weekly measurements is sufficient for getting athletes started and comfortable with the device. The goal should be to eventually get them to take daily measurements as this will provide more complete information including sRPE, daily sleep score and comments. The comments section is highly underrated and I intend to elaborate more on it’s value in a future post.

HRV Reflects Detraining – Trend Analysis

Generally when I see a decline in my HRV trend it is because of illness, high stress or significant accumulation of fatigue. However, over the Christmas break I decided to take 2 weeks off from lifting. This decision was based mostly on the fact that I wouldn’t have access to my training facility until after the break. The last time I remember taking this much time off from lifting was back in 2006 when my appendix ruptured and I didn’t get to a hospital until about a 10 days later. I have a nice 6 inch scar on my lower right abdomen to remind me to go see a doctor sooner than later when I feel really sick. Needless to say I was forced to take some time off.

Below are some screen shots of my data that clearly show a steady decline in my HRV trend after approximately one week of training cessation.

RPE Trend Jan 10

–          Above you can see that my last workout before the break was on 12/21 and my first workout back was this Monday (01/07). Between those dates I performed 4 body weight workouts that were largely half-assed. I think my rationale for them was to justify eating all of those high calories meals over the holidays. Without these mini workouts I believe the trend would’ve shown a steeper decline.  HRV baseline dropped from about 80 to about 74 by the end of the detraining period.

–          The steepest dip in the trend came on New Year’s Day as a result of the overeating and drinking from New Year’s Eve. HRV responds poorly to partying.

–          The high point on 01/03 I believe was the result of a day that included a 1 hour massage, hot pools, sauna, steam room, cold tub etc.

–          Training resumed 01/07 and as expected strength levels were noticeably down and a workout that previously could be considered a deload was rated as an 8 and caused a pronounced dip in HRV the following day accompanied with extreme soreness. A clear sign that I’ve detrained. The same happened for Wedneday’s workout (01/09).

Data Jan 10

–          In the image above you can see that my HRV is lower than usual (baseline is typically around 80). 01/04 stands out to me as a HR of 61.4 is usually accompanied with a high 70’s – low 80’s HRV score but instead HRV is at 72.

trend change Jan 10

–          Above you can see my 3 month trend charted and my Daily, Week and Month change. You can clearly see my baseline HRV steadily decline in late December.

I can think of 2 stuides that investigated the effects of detraining on HRV.

In a study by Gamelin et al (2007), healthy young men (untrained, age 21) were put through 12 weeks of aerobic training followed by 8 weeks of detraining to determine its effect on HRV. An improvement in HRV was seen after the 12 weeks however HRV scores returned to pre-test levels after only 2 weeks of training cessation. “Twelve weeks of aerobic training are sufficient to achieve substantial changes in Heart Rate Variability; and only two weeks of detraining completely reverse these adaptations.”

–          My declining trend in HRV was reflecting my fitness levels, not my strength levels even though they also declined. My trend would’ve likely remained relatively unchanged had I maintained aerobic fitness.

In a recent study by Gutin et al. (2012), obese children were put through a 4 month exercise intervention. RMSSD (a time domain measure of parasympathetic tone) increased after the exercise period and decreased during the detraining period. Below are some excerpts from the study I felt were worth sharing;

“The variables that were significantly associated with individual differences in responsivity to the PT were: (1) the pre-PT RMSSD level—higher pre-PT values were associated with lower change scores (r= −0.28, p = 0.018);”

–          I’m curious to know what accounted for higher pre-training RMSSD values in those subjects. Were they more fit? Were stress levels just considerably lower? Is this a genetic thing? How does resting RMSSD pre-training effect training response? In research I discussed here, higher HRV levels pre-training resulted in larger improvements in fitness vs. the subjects with lower HRV levels pre-training in recreational endurance athletes (Vesterinen et al. (2011) and in soccer players (Oliveira et al. 2012).

“the change in vigorous physical activity (r = 0.25, p = 0.040)—those who increased most in vigorous activity increased most in RMSSD.”

“The primary result of this study was that the RMSSD increased during 4-month periods during which the obese children were engaged in PT, and declined in the 4-month period following cessation of PT in Group 1. This demonstration of what occurred as a result of increases and decreases in controlled vigorous activity supports the idea that regular exercise has a favorable influence on PSA in this population. “

–          These results obviously aren’t shocking and we don’t need HRV to tell us we are detrained. However, monitoring the trends allows us to ensure favorable responses to training. This becomes much more important in athletes or individuals engaging in intense physical training.

Wrap up

Only two weeks of training cessation will result in noticeable decrements in performance and a decrease in resting parasympathetic tone. In the future I will likely perform 1-2 maintenance type workouts each week to maintain strength and fitness levels.

References:

Gamelin, et al. (2007) Effect of training and detraining on HRV in healthy young men. International Journal of Sports Medicine, 28(7): 564-70

Gutin, B., et al. (2012) Heart rate variability in obese children: Relations to total body and visceral adiposity and relations to physical training and detraining. Obesity Research, 8(1): 12-19

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

Vesterinen, V. et al. (2011) Heart rate variability in prediction of individual adaptation to endurance training in recreational endurance athletes. Scandinavian Journal of Medicine & Science in Sports, DOI: 10.1111/j.1600-0838.2011.01365.x

Recent HRV trend analysis and a new collaboration

As I try and further my understanding of the seeming incomprehensible autonomic nervous system I try to simplify the role HRV may play in monitoring athletes. There is one main issue I’m having; I don’t yet fully grasp the ANS (does anyone?) and therefore I still have a ton of unanswered questions.

I’ve noticed that there are some extremely intelligent people who are strong advocates of HRV usage as a monitoring tool. I’ve also noticed there are equally as intelligent people who are very skeptical and even doubtful of its efficacy and applicability. I’m doing my best to understand both sides of this argument. The best I can do to contribute to this discussion (at the moment) is draw attention to research and offer personal experience.

It’s been a while since I’ve posted and discussed some of my HRV trends so today I will do this as well as share some observations a colleague of mine has made at McMaster University.

Below is a screen shot of my HRV trend from the last 30 days:

  • Horziontal Blue Line = HRV Baseline
  • Vertical Purple Bars = sRPE (absence of these indicate no training)
  • White Lines = Day to day HRV scores

Training structure has been as follows:

  • Monday – Squat
  • Tuesday – Active Recovery
  • Wednesday – Bench Press
  • Thursday – Active Recovery
  • Friday – Deadlift
  • Saturday – Off
  • Sunday – Off

Strength workouts range from an RPE rating of 7-9 while the low intensity “recovery” days range between 3-5.

dec 2012 trend

Observations:

  • Much of what I’ve seen is consistent with what I documented in this post so I won’t discuss these in too much depth again.
  • Normally my HRV will be at or above baseline after a weekend (no training). In the first weekend you see my HRV dropped quite a bit Monday morning. I assume this is because I was away that weekend and I spent much of Sunday in the car and then was frantically trying to get caught up on things once I got home before Monday.
  • I trained at an sRPE of 8 on Monday and as expected another drop and a red indication for Tuesday. Active recovery typically will bump HRV back up the next day however Tuesday night I unknowingly went to sleep with my friends cat hiding under my bed. Around 2am I got a startling wake up as the animal tried to snuggle with my face. It took me nearly 2 hours to fall back asleep after. HRV that morning is another red and I feel like crap. I take a deload day on Bench  (sRPE 7), sleep well and HRV comes back up the next morning.
  • Things remain consistent during the week shown in the middle of the trend. Moderate dips in HRV in response to sRPE 8’s with returns to baseline after low intensity days. HRV is high after a restful weekend.
  • The following week I start doing a little more work in my workouts (more heavy sets) and therefore a higher sRPE rating (of 9). Along with higher amounts of soreness and perceived fatigue I saw larger dips in HRV the following day. On Friday (deadlift day) I keep things conservative due to previous lower back injuries and perform an sRPE of 8 and see less of a drop in HRV the next day. I’m happy to report that the back has been feeling good and I have started deadlifting again recently. I stopped deadlifting  for a while as I was experiencing pain during the lift (no surprise it was an underactive multifidus) Video below of a recent deadlift.
  • HRV is high after a restful weekend. sRPE of 9 on Monday (squat) of the last week shown on the image and I again see a larger dip in HRV (today). Will do some low intensity stuff later on after work.

Collaborating with Steve Lidstone at McMaster University

Since moving back to Canada I’ve been working on getting an HRV project going with Steve Lidstone, the head strength coach at McMaster University (a huge rival of mine in my football days). After some e-mail discussions I sent Steve an ithlete to try out. After a few weeks Steve sent me this update;

“I’ve been monitoring my HRV for 3 weeks now every morning.

I started off with HRV at 88 with a HR of 60bpm.

In times of poor sleep (we have 2 kids ages 2 & 4) or high stress my HRV has plummeted to 55 and resting HR of 79.

It is also interesting to me as I am in my 5th week of post concussion symptoms. When my HRV is low my symptoms are escalated.”

At this point we’re looking at getting two of his teams started with ithlete (about 8 players in total). Should make for some good data to discuss.

HRV Guided Training, Periodization and Training Variables

Here are some things to consider when planning your daily workouts guided by HRV;

  1. What load of work can my body handle today?

    I primarily use HRV to determine this, however lately I’ve been doing some morning tap tests as well to see what I find (Tap Test App for iPod).

    I like to break adaptive capacity rating up into 4 categories

    1. High – Increase loads
    2. Baseline – Proceed with planned load (moderate to high)
    3. Below Baseline – Reduce load
    4. Low – Rest or Active Recovery

      *In this context load refers to a combination of volume and intensity of training

    iThlete provides color indications for each of these days to simplify interpretation;

    1. Green = High
    2. White = Baseline
    3. Amber = Below Baseline
    4. Red = Low

      Here is a “Baseline” HRV Score measured this morning

  2. What is the goal of the current training phase?

    Accumulation of volume? Intensity? Weight gain? Weight loss?

Your training plan will obviously reflect your training goal however I’ve learned that it’s wise to make necessary adjustments to load in response to the present day’s adaptation potential. The following are a list of variables that I like to manipulate on a daily basis according to HRV score within the context of the training phase/goal.

  1. Volume (number of sets and reps performed with the main lift and assistance work)
  2. Intensity (the amount of weight on the bar)
  3. Rating of Perceived Exertion (how close to failure I get with my sets)

Here is an example of how I manipulate these variables based on training phase and HRV score.

Example: Volume Phase in a Block Training system:

I consider total reps in the 15+ rep range (usually no more than 25 total reps) to be high volume. This can be 3×5, 5×3, 4×4, 5×4, 6×4, 7×3, etc.

  • If HRV is high: I will typically take the higher end of the volume scale using higher sets and lower reps. RPE falls between 9-10 (10 only on last set).
  • If HRV is baseline: I will work in the middle set/rep range of the volume scale. RPE stays around 9.
  • If HRV is below baseline: I’ll stick with the lower end of the volume scale (no more than 15 total reps) with RPE staying around 8.
  • If HRV is low: Active Recovery work, no lifting.

With this set up I can still accumulate volume as long as HRV isn’t low. If I take care of my sleep, eating and overall stress levels, low day’s usually only occur the day following a training session. This is why I lift every other day and perform active recovery on “off” days. The idea is to increase the volume when HRV is high with higher intensities (<3 reps, higher RPE). When HRV isn’t quite where we would like it, we still accumulate volume, but with less intensity and a lower RPE.

Another method I’ve used for manipulating loads on a daily basis is to use more of an undulating periodization approach as opposed to a block approach. With this approach volume, intensity and RPE are constantly changing from workout to workout.

Example Undulating Periodization Approach;

  • If HRV is high: Both volume and intensity will be higher (ex: 6×2 with RPE 9-10)
  • If HRV is baseline: Reduce volume OR intensity (ex: 3×3 with RPE 9 or 3×8 RPE 8)
  • If HRV is below baseline: Intensity AND volume is reduced (ex: 2×4 RPE 8)
  • If HRV is low: Deload workout/active recovery

With this system we increase total load when the body is prepared to handle it better and back it off when necessary. Higher HRV days will involve lower rep ranges to allow for a higher %of 1RM whereas lower HRV days will have higher reps to reduce % of 1RM.

Keep in mind these set ups were for the purposes of increasing strength. Through constant experimentation and evaluation I’m improving on my approach to training. These set-ups aren’t perfect but they worked well. I’m presently using the block approach illustrated in my first example in my current training.

In a few weeks I’ll hopefully get a good post up on how the tap test fits into my program design. I’m looking to see how it correlates to strength, HRV, RPE, etc.

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.