It seems like energy system training is a hot topic these days and one of the debates currently undertaking the profession is centered around the idea of programming workouts based on internal or external training factors.
For those that are unfamiliar with those terms, for the most part, external training loads are things that the athlete does in training (running/cycling pace, loads/intensities, sets, reps, GPS Data, etc) while internal training loads are the athletes response to training (HR response, session Rating of Perceived Exertion, subjective reporting of how they feel, etc).
The argument stems from people basically taking sides as to which is more important when it comes to programming training:
- Internal Monitoring – Programming based off of HR response or HR zones as a means of prescribing intensity.
- External Monitoring - Programming based off of pace/velocity/Watts as a means prescribing intensity.
I believe there is value in both arguments.
On the one hand, prescribing based on pace/velocity/Watts is helpful because it is specific to a percentage of the athlete’s max output during the race/test they are being asked to perform. To improve that output it makes sense to train at certain percentages and slowly build up the capacity to set a new PR. This is similar to lifting weights based on a percentage of your 1RM as a means of attempting to increase your capacity to handle greater loads.
On the other hand, prescribing based on HR response can be helpful because it allows you to understand how that athlete is tolerating training “under the hood”. There is always a cost of doing business when we train. Some athletes can pay back that cost and recover faster than others. One thing internal training monitoring, in this case HR response, does is help us understand what that potential cost is and dial down the workout (or dial it up) based on how the individual is responding.
Why Not Both?
Why does it have to be an either or discussion? Like most disagreements in our profession topics tend to get polarized very fast and people chose sides. I think the true answer probably lies somewhere in the middle – most of the time.
I try and think about energy system training from both sides of the equation as both can be informative. I find great value in programming running or cycling workouts based on velocity or Watts as it is very specific to what the athlete is supposed to accomplish for a given time frame or workload. However, I find a huge benefit in also evaluating the internal response the athlete has to that training session.
For example, prescribing interval runs at 85% allows me to dictate the intensity of the session from an output side of things. Evaluating HR response lets me know a few things:
- The individuals response to the workout – 85% may produce very different HR responses from different athletes.
- Any atypical response the athlete may have - If I start to understand what a normal response is for that athlete to certain workouts I can then begin to understand (a) how much to load the athlete to get a certain result and (b) when the athlete may be fatigued or producing an atypical HR response to an intensity that should not be as challenging to them.
- Potential Aerobic Improvements - Sort of piggybacking off of point 2, if the athlete begins to have a favorable physiological response to the prescribed intensity (IE, it is less difficult or the cost of performing that given workout is decreased while performance has increased) this may signal time for a change or perhaps a re-test of the athletes fitness level.
There are many ways to monitor an athlete’s training session. While people tend to chose sides I believe their is a benefit to looking at both external and internal variables when prescribing energy system training. As technology begins to offer us the ability to capture just about anything and everything I still contend that a good, detailed training log is one of the most valuable things an athlete can keep (it is also relatively free save for the cost of a pen and notebook). Charting simple things like training intensity and physiological response overtime can provide the coach with a quick understanding of how the athlete is tolerating the stress of training and whether or not changes to the program need to be made.