By: Matt Larson, USAC Level 2 coach
First, let me briefly describe what I see as the primary advantages of power training:
1) Power allows you to train with great specificity.
2) Power responds immediately to rider input.
3) Power training zones can change dramatically over time with both improvements in fitness and as a result of detraining (losing fitness either planned or accidently).
Each of these advantages have “behind the scenes” benefits for your coach, so let’s review each of these in some detail from a coaching perspective:
Power allows you to train with great specificity
In our training methodology at AthletiCamps, we utilize 7 heart rate and/or wattage training zones based on an athlete’s lactate threshold heart rate and wattage. Each of these zones has fairly sizeable and therefore real-life practical, range, for example, our Medium Endurance (Tempo) zone can have about a 10 bpm range (e.g., 150-160 bpm) for HR, and a 20 watt range (e.g., 225-245w) for power training. While I will frequently assign an athlete a workout that asks them to do multiple intervals in this zone, I’ve found it much easier for athletes to stay at a given wattage than it is to stay at a given HR, partly because HR is less accurate of an indicator of effort than is power.
With power, there’s a greater ability to fine tune workouts in a way that’s very difficult to do with HR. For example, I can ask my athletes to ride at 275w for 10 minutes, while the best I can do with HR is to ask that they stay within a 10 bpm range. While it is true that moment-to-moment wattage varies much more than with HR, I find that at the end of a block of time, riders will average within 5 watts of what I’d specified, a level of precision that’s much harder with HR.
For our “progressive intervals” where we incrementally increase the difficulty of the interval every minute (as an example), or “over/under” intervals where we have the athlete spend blocks of time immediately above and below their lactate threshold, prescribing a wattage target for these workouts is generally much more successful than prescribing HR ranges because of significant heart rate lag (by the time you’ve recovered from your “over” lactate block, your “under” lactate block can be ended.)
Power responds immediately to rider input
As anyone who has used a power meter knows, the watts we see displayed on our bike computers have an almost immediate relationship with the amount of force and/or cadence we’re putting into the pedals. With HR, there is potential for various lag times between effort and change in HR. Imagine climbing a hill at either 170 bpm or 300 watts. Once you crest the hill, your HR takes quite a while (depending on fitness) to return to recovery levels. With wattage, the moment you crest the hill and start soft-pedaling your wattage drops to zero.
From a coaching perspective, this allows me to tailor workouts in a much more delineated way. If I ask my athlete to spend 5 minutes at 300 watts and then recover at 100 watts for one minute, I know that their power output can be altered almost immediately. With HR, it is much harder for the coach to really know how much time an athlete is spending in a given zone because of this lag between rider input and HR.
Power training zones can change dramatically over time with improvements in fitness
Once an athlete is relatively fit, their HR zones change little or none over time regardless of changes in fitness. However, if an athlete continues to get fit, their power zones will continue to improve (i.e., more power at a given HR). Thus, after a relatively short period of time, it is extremely difficult for a coach to utilize an athlete’s HR to track changes in fitness.
With power, however, changes in fitness are easy for the coach to see. In looking at an athlete’s power files over time, the coach can notice whether the athlete is producing more power at a given HR. If this is the case (and we all certainly hope this happens for a long time!) the coach can modify the wattage training zones and thus easily recalibrate the athlete’s training.
With HR this is literally impossible. Every athlete has a functional maximum HR (usually seen during racing). For younger athletes, that max HR won’t change for many years. For much older athletes, that max HR will slowly drift lower over time. Similarly, Lactate Threshold HR stays fairly stable in fit athletes. Whether the training program prescribes workouts based on threshold or maximal HR, either way, there’s no reason to alter those zones once an athlete is fit. Thus, the only way to see improvement is in race results (where a lot of external variables are present aside from fitness), field testing (where there are also external variables that can influence performance) or lab testing (which can be relatively expensive or inconvenient to do with regularity).
Riding with power yields more and better data for the coach to analyze
Most coaches whose athletes use power, also use software to help them analyze the data. There are several terrific programs out on the market, but a review of the software itself is beyond the scope of this article. Suffice it to say, if the coach wishes to do so, they can perform a pedal-stroke by pedal-stroke analysis of their athlete’s ride data. While this level of detailed analysis is rarely needed, having the option to really drill down into the ride is a very powerful tool for coaching. There’s much a coach can learn simply from looking at a basic summary of the ride: whether the athlete followed the workout, whether they were able to “hit their numbers”, whether there’s an overall trend towards improvement in wattages, and whether the athlete is in danger of overtraining.
A critical side-note: athlete files are useful to the coach only to the degree that the athlete “marks-up” their ride file. While not every software program allows this to happen, every athlete can, at minimum, create a new “lap” or “interval” when they switch from one portion of the workout to the next (e.g., from hill intervals to recovery mode).
Riding with power creates a greater opportunity to expand the coach-athlete relationship
This point is directly related to the previous one in that being able to analyze power files gives the coach much more information with which to help guide their athlete. It also opens the door to having significantly more detailed conversations about training. For example, in reviewing a power file, I noticed that one of my athlete’s wattage dropped when they were above and below a certain cadence range. Having made this observation and pointed it out to the athlete, we were able to get into a conversation about natural cadence. The athlete had been trying to stay within my prescribed cadence ranges in the workout, but these were not successful for him. After a review of the data and discussion with the athlete, we were able to revise his use of cadence and increase his overall wattage production.
There are several notable benefits for your coach when you use a power meter as a training tool. Almost all of these benefits are related to the immediacy of changes in wattage as related to pedal force. From a coaching perspective, while HR is a tried and true means to train (and one I still use along with power), the specificity of training with power cannot be beaten. Of course, all of these benefits are moot if the athlete doesn’t send power files to their coach on a very consistent basis. In fact, the way to maximize what your coach can offer you in terms of power training is to make sure that your coach has all of your power files!
Bike coaching is unique amongst sports coaching endeavors primarily because of the availability of power. While this article is not meant to discourage anyone from using HR as a training tool, from a coaching perspective, power is the way to go!
May you produce ever more watts!
Matt Larson is a USAC Level 2 Cycling Coach and proudly works for AthletiCamps. Find out more at www.athleticamps.com and check out the AthletiCamps Blog.