What can HR monitors really measure ?? (Suunto T6)

[billw]

Hello,

There have been some posts about the multi function Suunto T6 recently, which have prompted this post. Am intrigued and will send this question to Suunto as well.

Please understand I am very keen to better understand this. Am not trying to criticise or belittle Suunto or the people who use this product.

Am keen to get some feedback from Suunto users and debate going regarding what you can and cannot expect a HRM to tell you - Frankly I dont know and am genuinely interested and if convinced may purchase a T6.

So here is my question - Some of the graphs produced look fairly similar -If the T6 accurately measures time between each heartbeat and then calculates 7 different things isnt it only measuring 1 thing and reporting it 7 different ways via 7 different correlations ?

It is fairly easy to calculate a huge number of indexes from any set of 4200 data points (30' x 140 bpm).

Before anybody flames me - I freely admit that figuring out these 7 equations and implementing them in a software package is a significant achievement in itself - I simply want to establish whether or not it is actually measuring 7 different things or just measuring 1 thing and then running 7 different equations using the same data as input. At the moment it seems to me to be the latter.

So are there people out there monitoring the 7 values and using that feedback to influence the next training session ? If not 7 values then which ones ?

I think one issue regarding what you can expect from your HRM is what data is gathered - ie
Cheaper Monitors - simple average of HR over X seconds
Expensive Monitors - time between each heartbeat


Final question - does the information gained from the 7 parameters significantly affect your next session ?


Regards

Bill

[mpukita]

Bill:

Think of it this way. Older HRM technology monitors only measure HR over time, and extrapolate from that. One set of data points. The Suunto monitors HR & HRV (variability or RR). The t6 has now DOUBLED the usable data we have available to measure, extrapolate, or manipulate to understand your current level and "breadth" of fitness, the impact of a workout, and how to plan future workouts.

Additionally, you should be getting as accurate as possible with the other variables that you have must set in the software to get the results from these "seven equations" -- things like VO2 max, METS, etc. For those that cannot get this measured, Suunto helps one estimate these parameters, Over time, you will "figure these out" -- what these should be -- because many are ratios of other measurements. If you take the time to learn the relationships (like Eddie Fletcher has), you'll come to know, with great accuracy, where you should be (conversely, you'll come to see that one or more are "out of whack").

There is no question that there is great benefit in using the watch to structure training. For example, I did a 2x6K90sR yesterday that was stroke rate and HR "capped". This is EXACTLY the same workout I did on 8/29 (excuse the US date format!) and 8/31. I have been doing plenty of training since 8/31, yet the 8/31 raw numbers -- average pace and rate -- were BETTER on 8/31 than yesterday. I was about a second slower in average pace for the two 6K's yesterday. I was a bit disappointed at first. Then, I overlaid the 3 workouts and saw that my fatigue (measured as RR by the Suunto) was MUCH higher yesterday -- right from the very start of the workout -- than for either prior workout. I also saw that the training effect ... how the workout impacted my aerobic fitness, was HIGHER than either prior workout. Thus the expression, "You don't have to train fast to race fast."

Normally, in the "old world", I would have been disappointed and put in place "corrective action" to make up for this fall in pace and perceived fall in fitness. I might have done a long row today -- continuous 15K to 20K. Because I would have assumed my aerobic fitness had become diminished since 8/31. This would have been the absolute WRONG thing to do. Actually, better to rest than to do 15K to 20K. It would have been "defective action" instead of "corrective action".

Those of us that are older, and Type-A to boot, have a hard time with this. Eddie and the results from the watch have convinced me that a more scientific approach to training, especially as a "mature" athlete, has to be taken to avoid over training, excessive fatigue, pointless workouts, and sheer disappointment.

And believe me, this isn't some way to get out of training. My plan has me rowing 75K to 80K each week, with w/u and c/d, but just about every meter is worked to a stroke rate, HR cap, and then pace ... in that order.

The proof will be in the pudding, for me, this season at BIRC, EIRC, and WIRC. Once I've raced these, under Eddie's guidance and using the Suunto t6, I'll share a summary of what we did, and how we did it, and what resulted. I am cautiously optimistic about a slowly, methodically improving level of fitness, and therefore 2K times. I can "see" it from the Suunto, the question will be can I translate it into racing results? I believe I can,

You should also search on "Suunto" both here, and on the UK forum, to get more good information.

Regards -- Mark

[billw]

Mark,

Thanks for the answer.

Will enjoy reading your summary afetr the three championships.

Bill

[Eddie Fletcher]

Bill

Where to start!

It's not 1 thing reported seven 7 different ways!!

Each varaible (HR, HRV, EPOC, VO2, VE, RespR) are based on your own personal physiology together with the background equations - different physiological factors are used independently and together to get data for each variable.

Each variable can be used in a number of ways depending on the duration, stroke rate, HR and phasing of the training. Some variables are more useful than others again depending on the session.

For example a for long duration session EPOC linked to VO2 would be the most useful measures of intensity and for short interval work VO2 becomes the most reliable measure of intensity.

The data is only as good as the background personal information so you need to know or test - rest HR, Max HR, height, weight, age, activity level, VO2max, vital capacity etc to get the most out of the software (most of these parameters are easy to test/estimate for 2k rowers). The software estimates are reasonably accurate.

You also need to know something about periodisation so that when looking at an individual session you know whether it is at the correct level for the phase of training. Following a structured training programme is essential.

For example it easy to be mislead by the EPOC descriptions which all have positive names such as improving, highly improving - they are also indications of over training/ under recovery if the software downgrades your activity level i.e. you are losing fitness!

There is so much to this piece of kit that it is impossible to do justice to it in short forum posts - I have a Guide out this week avaiable from C2 (UK) or myself price is £7.50 (post free in UK - will look into USA postage tomorow) - answers many of the questions.

I will try and respond to individual Suunto t6 questions posted on the forum but they will need to be very specific!

[johnlvs2run]

for short interval work VO2 becomes the most reliable measure.

Vo2 is a result of work output, not a predictor or measure of performance.

[sledgehammer]

Eddie & al - Just curious,

Have any independent scientists published studies that support the value of HRV (hear rate variability) as a legitimate analytical tool?

Sounds cool to me, and I love gizmos but I remember high school football coaches telling me to eat salt tablets during practice, and high school wrestling coaches telling me that it was OK to dehydrate myself in order to "make weight". Both now seem like pure dumb logic in hindsight.

Probably not great analogies....but my an attempt to ask whether the concept of HRV has stood the test of time (and smart people).

Thanks in advance, Ernie

[Eddie Fletcher]

John

You misunderstand my terminology. % of VO2max can be used as a measure of the intensity of a session. I've amended my post accordingly. I haven't use the words 'predictive' or 'performance'

Sledgehammer - the simple answer is yes - I'm writing a review article for a publication which I will reference on this site in the future (will not be until late November) - in the meantime some of the references can be found in the back of the Suunto Training Guidebook

[hkp2ksk]

a really nice primer on VO2 can be found at:

http://www.coolrunning.com/major/97/tra ... mpson.html

tony

[johnlvs2run]

% of VO2max can be used as a measure of the intensity of a session.

How did I misunderstand, when you said the same thing again.

[Eddie Fletcher]

John

Definition of VO2max is simply maximum amount of oxygen consumed each minute of maximal exercise. HR and VO2max have, generally, a linear relationship.

You can express exercise intensity in a number of ways one of which is relative metabolic level expressed as percentage of VO2max (i.e. 80% of VO2max) and you can also convert VO2max into multiples of resting metabolic rate (METs - i.e. 8 METs).

So it is possible to establish an aerobic training intensity via direct measurement of (or estimation) of VO2max and HR.

Unless you have a Suunto t6 and understand the underlying basis this may not have much meaning for you.

[mpukita]

John:

Why must you be an ass on every topic on the forum?

The unfortunate part of your behaviour is that you are rarely correct or accurate. Your ability to disseminate and promote incorrect and erroneous information is simply a miracle. Your ability to be rude is simply bad manners.

How about going somewhere, anywhere, else, unless you have something positive to add. I would venture to say that just about 100% of the people here are sick of your crap.

-- Mark

[dennish]

Mark, Just to cheer you uup. Went to Summit County this last weekend to get a high altitude ride. No dice, four inches in Summit County. Wax 'em up. dennis
PS the Buffs are also working on a perfect season

[mpukita]

Ernie:

Search "heart rate variability" on Google, and you'll get more abstracts and information than you can read in half a lifetime. Such as:

http://www.macses.ucsf.edu/Research/All ... .rate.html

http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract

Heavy stuff (for me at least).

The bottom line is that you can watch this measure in workouts and know why you might be slower, at same rate, pace, and duration, on any given day. It makes for better comparison of "like for like" workouts vs. fatigue. It helps older, Type-A (me?) athletes avoid over training.

Here are four traces of the same workout:

http://www.dropshots.com/day.php?userid ... ime=195704

Hopefully, you can see that paces and rates for these to see that they are very, very similar.

The "lower" the RR curve (heart rate variability), the more fatigue that's indicated. The "highest" line on the page indicates the least amount of fatigue using RR/HRV.

The interesting thing here is that the performance level is matched to fatigue, and each of these workouts had very similar training effects and EPOC. The fastest was done in week one of a new training program, after 2 or 3 workouts of moderate duration, pace, and rate.

The final two were done this week. The "worst" (slowest) was done two days ago, after a smoking (for me) 5 x 2K workout the day before, and an interval workout of shorter distance pieces the day before that. It is absolutely clear that I was much more fatigued that day. Look at the starting heart rate - 120 or so -- after the same exact warm-up I do for every workout like this! Normal start = about 90.

Today, I did the same workout, after another pyramid workout yesterday, but a great sleep and longer rest. I usually do my workouts prior to noon -- today's was later in the day -- more recovery time. You can see the difference, and I expected it. But, I expected it because I've seen how this all fits together using the t6. Before, as I said before, I would have been "disappointed" with the workout 2 days ago, and KILLED myself yesterday -- defective reasoning as I was fatigued and needed rest rather than a hard workout to "make things right".

Who out there hasn't felt the same way? My bet is that more than 50% of the time when they do, like me, they do the wrong thing in terms of what it takes to improve performance.

-- Mark

[johnlvs2run]

John:

Why must I be an ass all the time?

-- Mark

I don't know, were you born that way?

[mpukita]

Mark, Just to cheer you uup. Went to Summit County this last weekend to get a high altitude ride. No dice, four inches in Summit County. Wax 'em up. dennis
PS the Buffs are also working on a perfect season

Dennis:

Cool. I'm booked for Frisco again, and the Model-C's in Silverthorne, around the Super Bowl weekend ... my secret "high altitude" training week shortly before WIRC.



I also have a heli-ski week booked in BC -- in April -- first time for me. Pretty excited about the snow beginning to fly. I watch the web cams on I-70 and I saw that there was snow on Vail Pass last week.

As we say, "On a powder day, we wait for nobody."



-- Mark