*UPDATE* Psychological Effects of Heart Rate Monitor Use Study

12/21/2010: Preliminary results were reported at Indoor Cycle Instructor in October 2010. Manuscript in preparation. Once published, results will be made available on this site and at ICI.

Sunday, July 6, 2008

Analogue between "Rate of Perceived Exertion" (RPE) Scale & % MHR

I refuse to engage in 99% of physical activities without wearing my heart rate monitor. A heart rate monitor is a tool that provides objective feedback of your physiological response to intensity/challenge. Just as I would never drive my car without a speedometer, I don't drive my heart without a heart rate monitor.

In my NYC classes, most of my students wear HRMs to class. In Burlington, this will not be the case. So I need to get more comfortable coaching to a Rate of Perceived Exertion (RPE) scale to give those without HRMs a construct by which to gauge their intensity.

And truth be told, all HRM-wearers are best served maintaining an awareness of RPE even as they train with their HRM's. If there is a mismatch between HR and RPE, this is an important clue to an underlying situation: overtraining, fatigue, volume depletion, certain medications influencing heart rate. Don't ignore it. Under those conditions, RPE is actually MORE useful than your heart rate monitor.

Before I describe how I use a 0-10 RPE scale in my classes, I'd like to discuss a few issues on my mind:

1) Lack of proper usage
* "Resistance scales"
There are no scales of resistance level!!!
Ever hear this one?: "Give me a 9 out of 10 of resistance" >> no, guys, there are NO scales of resistance. It is actually a "taboo" contraindication of the body that certifies Spinning instructors, in fact. Resistance loading is ENTIRELY arbitrary and subjective. Every bike is different, every person is different. We don't care about a specific amount of resistance -- we care about using enough resistance to achieve a certain intensity. The intensity is what we want to measure and monitor -- that's what impacts your training. Anyone who uses a scale of resistance is doing you a great disservice, and my professional opinion is that you should ignore them.
* Be skeptical. Since you are educated athletes (and you all are), think about it: Why would we want to hold what is described as a "10" for a long period of time to climb a normal, run of the mill hill?
* Be safe. Warming up is so key to not only safety but the efficacy of training. If you spike the HR too early, you will actually have trouble recovering throughout the training session. I experience this *all* the time: all those times that I say I'm coaching entirely off-bike (as in the case when I'm teaching 5 classes in a single day, for example) and then I randomly hop on the bike to do an anaerobic interval with you - my HR spikes without warming up, and I'm a cardiovascular mess all day long. That said, anyone who takes you from the warm-up effort to what he or she calls a "9" without any intermediate stops along the way: also doing you a great disservice. Our hearts, like our minds, prefer consistency -- we try to avoid dramatic change. We like change -- in fact, we love change -- but we are better able to cope with change... physiologically, not just psychologically... by doing so gradually.

2) Lack of consistency

Here is a chart that I made to help link RPE parameters with verbal descriptors, and heart rate parameters. Remember that most people have not and will not ever experience their MHR, and that MHR formulas are inaccurate. I recommend finding lactate threshold (8/10) through a lactate threshold/submax field test, and setting LT = 85% MHR. Reverse-calculate MHR and take percentages from there. Effectively, your training parameters will be anchored to LT -- which is measurable, and modifiable with training.


Description – Standard Language with a Bit of Melissification



0 = in bed. 1-2 = Very easy – conversation not impacted whatsoever. Pre-warmup into beginning of warm-up




Easy. Conversing very very limited difficulty. Start of warm-up



Moderately easy – you can still carry on a full conversation but you're aware that you're actually riding a bike. End of warmup. Something you can hold *indefinitely*. Feels perfectly comfortable, literally able to sustain forever.



Moderate – carrying on conversation would require very minimal effort; a bit more concentration than at RPE 4. But you're very very comfortable. You're aware that you're riding a bike - and you can sustain your effort "all day, but not forever." Feels amazingly refreshing. You LOVE this.



Moderately difficult – conversation would require effort/concentration. You can do a lot more, but you’re working. Thinking that you don’t want to hold this all day. Feels good but not amazing.



Difficult. You can certainly talk - but carry a conversation? Unlikely. “Comfortably uncomfortable.” No burning in the legs; no tightness in the chest. You’re starting to think you not only don’t like this – but, in fact, you might actually hate this.



Very difficult. Lactate threshold = point at which lactic acid accumulation exceeds your body's ability to clear it. Burning in the legs might start. You HATE this. You truly hate this. Everything around you is telling you to stop -- but you don't. You can still track your breathing in through the nose, out through the mouth. All of your mental faculties are consumed tracking your breath and reminding yourself that you're not going to stop, even though you want to. Those new to training: can hold 1-3 minutes. Some conditioned athletes can hold as long as 30 minutes.



Peak effort I ever want you to hit in my classes. You have just enough wind to finish the effort (30 seconds max). Intense burning in the legs. Might feel breathless. You hate this SO much. By the 31st second, it HAS to be over -- so it is. (Make sure you recover back down to 4/10 before you hit this intensity again, for an effective anaerobic interval.)



Heart is going to explode out of chest. Might feel dizzy or nauseated. STOP. STOP STOP STOP.



A said...

Wear my HRM 24/7, but do occasionally lose track of my strap...like last nite (dang it)! Lovely, new British instructor, so I didn't walk right back out---though I did ignore her "ok, we're at at least 6 or 7 [out of 10]....in the first 90 seconds of the class (no exaggeration)! YGTBFKM! Nonetheless, 62-minute class and a fine workout for practicing breathing control...and verifying that even the instructor can't maintain a 180+bpm standing flat (wtf?!)...and the 275 lbs "big guy" will revert to a seated climb! Got back home + located my strap...in the driveway! Grrrr! ~jj

DaveyB said...

Hi Melissa - as a matter of interest does this mean you cue using the RPE as opposed to "add half a turn" etc?


Melissa Marotta said...

Hi Dave,
Thanks for writing. I actually never use the construct "add half a turn" etc., and I'd recommend against it (as does the Spinning program) for two major reasons: 1) Every bike is different - at my club, for example, the instructor bike requires 4 complete turns before one can detect a difference. Imagine? So "half a turn" to one person's bike might be something entirely different to another; 2) What matters is the intensity. So I might say, "add enough resistance so that you feel like you can hold this most of the day, but not all day." If it took a person half a turn more to reach that, or 4 turns -- it doesn't matter. The intensity (i.e., how hard we're working) is what matters. Then you can make adjustments - "load a subtle bit more resistance, not enough to slow you down, not enough to change your intensity - just enough to feel an extra pull in the back of your leg." Progressive loading drills like such can train people to get more work done without working harder - an important marker of efficiency and adaptation. Hope that helps!

DaveyB said...

Hi Melissa - thanks for the quick response...those cues are very helpful. It would be great to get an idea of the mapping of the cues you use to your RPE chart.

Thanks again. Great Blog by the way...not sure where you find the time though ;)

Melissa Marotta said...

Thanks - glad it's helpful! I wish I had more time to contribute as much new content as I used to. I'm a medical student, so time is getting trickier trickier.
Not sure what you mean by cue-mapping? The chart on this post has the language I use. Is that what you meant?

EXSwithSarah said...

Hello Melissa,
I am currently working on my methods section for my thesis and the RPE chart you provided is exactly what I am looking for (a 1-10 scale corresponding to percentages of Max HR). I was wondering if you had a source for that?