You hear the phrase all the time, “I’m a real minimum effective dose guy”, or, “We train only as much as we need and then no more”.
Everyone says these things, but what do they really mean? What is a “minimum effective dose”? Is the minimum effective dose different for different people? Do some people need more training and some less? While the phrases sound good on paper or when uttered at a training conference, how do we take the theory of the minimum effective dose and turn it into practice?
To be fair, these are great ideas and statements that really do resonate with me in my approach to program design. Why expend physical resources (energy) on training that are unnecessary and potentially limiting your recovery from the previous session, thus diminishing your ability to train harder the next time around? As I like to say, “There is always a cost of doing business. All training comes at a cost and in order to reap the benefits you need to make sure you pay that cost and then replenish the checking account before paying again.”
Recently, I had a great discussion with two colleagues I respect – Sam Leahey and Nate Brookreson. We were discussing concepts around an individualized training approach, and the main discussion points began with us first reading and talking over two papers by Kiviniemi, et al., Endurance Training Guided Individually by Daily Heart Rate Variability Measurements (Eur J Appl Physiol, 2007) and Daily Exercise Prescription on the Basis of HR Variability Among Men and Women (Med Sci Sports Exer, 2010).
Both studies utilized a similar type of training approach for the two training groups. One group performed a standard, predetermined training program – just like a coach would write for an athlete, dictating what should be done each day of the week (exercises, load/intensity, sets, reps, etc). The other group performed their training based on their HRV readings taken first thing in the morning, upon waking. The mode of exercise in the studies was endurance training, and days were broken into high intensity (40min at > 85% of maxHR) or low intensity (40min at 65-70% maxHR) or complete rest.
The way it worked for the HRV-dictated training group was that they would take their HRV, and based on the outcome, compared to a rolling average, they would alter their training for the day performing either a high intensity session, a low intensity session, or taking a rest day. Thus, training was guided by what the body was prepared to do.
Interestingly, the HRV-dictated training groups improved their fitness while training high intensity sessions less frequently during the study period than the predetermined training group (More is not better. Better is better). Basically, on days when their body was ready for a high intensity training session they went for it, and when their body was not ready they backed off and allowed the body time to replenish the checking out, so to speak, before repaying the cost. They gave the body what it needed.
Some of my thoughts
Heart Rate Variability is not the be-all-end-all of athlete monitoring, as some make it out to be. It is one small piece (a small piece with rather noisy data, mind you) in a much larger puzzle. That being said, I do believe it can have a role in athlete monitoring if you understand its limitations, standardize the collection process, and couple it with other methods of monitoring the athlete and evaluating their capability and capacity on a given day.
These studies seem to move us closer to understanding the concept of a minimal effective dose and perhaps offer a newer approach to program design and periodization – similar to the concept of auto-regulation. Earlier this year I put together a decision tree for training, similar to the one shown in one of the studies mentioned above, where a few factors were taken into consideration and put into the tree, and the results of those factors allowed the athlete to alter their training program based on the input they plugged in. This allowed us to adjust the program up or down on a given day based on how the athlete was responding. Instead of writing training programs that told the athlete to do “x” on Monday, “y” on Wednesday”, and “z” on Friday, the athlete was given different workouts with different training targets (2 workouts reflecting the main physiological targets of the training block, 1-2 workouts reflecting the secondary, or maintenance, physiological targets of the training block, and 1 recovery based work).
Depending on how the athlete was reporting that day, we would choose which workout to do. This would end up sometimes pushing our training week out longer than 7 days (sometimes it would take 10 days to get through the training cycle). This was apparent, particularly, in older athletes whose bodies took longer to recover from the training session or athletes who were out of shape and lacked fitness and needed the extra time to make appropriate adaptations to the training stimulus imposed upon them. If we were working on a timeline and had a set duration of time to perform a block of training (for example the athlete would only be able to train 10 weeks in an offseason), we would adjust the workout on a given day by lowering either training volume or training intensity (which of those we lowered was dependent on the physiological targets of that phase of training and what the main objective was).
What was also interesting in the studies above was that if the subject had recovered the following day from a high intensity training day they would then perform another high intensity session (although after two successive high intensity sessions they were asked to take a rest day). The high-low training concept of organizing high intensity stressors on one day and low intensity stressors on another day is a great one and one that I have used for many years; however, there are times when the athlete needs to be able to put together back-to-back days of high intensity work due to competition (i.e., basketball or hockey) or hard practices (i.e., NFL training camp) being stacked together. By using a training approach driven by monitoring the athlete’s response and adjusting the workout to suit their needs and abilities on a given day, we can slowly build up the athlete’s resilience to tolerate high intensity work to a level that allows them to train hard, recover quickly, and then train hard again. This is a key piece that ties together the stress resistance/stress tolerance and fitness components of my Physiological Buffer Zone methodology, which I discussed in THIS interview.
What it basically boils down to is that each athlete is an individual. Each athlete has a different way of responding and adapting to the training stress you apply to them (and even to the treatment stress if you are using soft tissue work!). The time it takes to recover and make favorable adaptations to a training session may differ from one athlete to the next, and an individualized approach, based on monitoring various qualities, is essential to understanding what the athlete needs. Too often coaches try and force fit an athlete into their training program without respecting these laws of individualization. Hopefully the future will allow for better methods to test athletes, monitor/evaluate athletes, and adjust training for athletes to ensure that their body receives the type of training it needs – the correct amount at the correct time.