Increasing heart BPM as a fitness gauge

AnnPT77 wrote: »

rodnichols69 wrote: »

Improving resting HR is the measure of fitness.

Increasing HR is not a sign of fitness and studies conclude that being close to max heart rate for long periods of time is more detrimental than beneficial.

That's interesting: Do you have a link to one of those studies?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC99308/

rodnichols69 wrote: »

AnnPT77 wrote: »

rodnichols69 wrote: »

Improving resting HR is the measure of fitness.

Increasing HR is not a sign of fitness and studies conclude that being close to max heart rate for long periods of time is more detrimental than beneficial.

That's interesting: Do you have a link to one of those studies?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC99308/

It seems to me as if that study is saying that recreational athletes – in this case hockey players – frequently exercise at an intensity that’s beyond the safe point for their current level of fitness/conditioning, not saying that intensity per se is always a foolishly risky thing.

That’s consistent with advice one frequently sees around here from experienced endurance athletes, saying that it’s risky for beginners to do high-intensity exercise such as HIIT, prior to developing a good cardiovascular fitness base. (Just doing intense exercise is not the best way to condition oneself to do such exercise more safely.)

In the study linked, they holter-monitor recreational hockey players, screening out any with known cardiovascular issues (they find a couple during the study who had such issues, but didn’t realize it). The holter monitor data shows participants' heart rate during the hockey games.

Their sample includes people who are, frankly, probably not in very good physical condition for intense exercise:

* Of the 106 participants whose BMI was determined, 58 (54.7%) had a BMI above 27. (page 5) That would be an overweight BMI.
* 70.1% of 114 individual monitored hockey games, showed heart rate had slowed by less than 12 beats/min at 1 minute after cessation of exercise. (page 6) A drop of 25-30 beats in the first minute would suggest good cardiovascular (CV) fitness, 50-60 would be excellent. 12 beats in the first minute would be . . . not very good at all, really.

Slow heart rate recovery (heart rate stays higher, longer, after exercise is over) is an indicator of poor conditioning and low fitness, not an effect of high exercise intensity per se. Periodically measuring one's own heart rate recovery is a standard part of assessing fitness progress, with faster heart rate recovery - heart rate dropping faster upon cessation of exercise - generally an indicator of improving CV fitness.

rodnichols69 wrote: »

Conclusion:
Exercising in a mild to moderate HR ranges is associated better fitness and fewer cardiac events.

Exercising above HR targets or age predicted MHR for extended periods of time is associated with poor HR recovery and increased risk of a cardiac events.

I was unable to find that stated as the conclusion, anywhere in the paper? (I see the ACSM caution referred to, but it's pretty de-contextualized, in some important ways, IMO.)

Basically, this seems to be a study aimed at figuring out whether recreational hockey players are commonly the sort of "weekend warrior" who undertake exercise intensities that exceed what would be most sensible for their current level of physical fitness. (In this sense, they might be comparable to the type of person who undertakes heavy snow-shoveling without adequate fitness, for example). With some very explicitly stated limitations about the size of the study and limitations of their testing mechanisms, the study finds that these presumably-typical recreational hockey players do take what the researchers consider risks. Further, it gives some strong indications that proper conditioning (that “building base CV fitness” thing) is protective against CV incident risk from overexertion.

Here’s an extended quote from study , bolded by me (with footnote numbers removed for readability), to show why I think that:

The American College of Sports Medicine recommends an intensity of training from 55% or 65% to 90% of age-predicted HRmax. The college further cautions that “Higher-intensity exercise is associated with greater cardiovascular risk and orthopaedic injury.” Although the benefits of exercise are widely recognized, there have also been reports of an increase in frequency of cardiac events and sudden death triggered by vigorous exercise. Regular exercise seems to diminish this risk.

It is important to emphasize that no adverse events occurred during our study. Franklin and colleagues reported that moderate to vigorous exercise was associated with a mortality rate of 1 per 50 000 among people who exercised infrequently, a rate above that in the general population.

Willich and collaborators, in a retrospective analysis, found that 7.1% of patients who presented with myocardial infarction but only 3.9% of the control group were engaged in physical exertion at the time of the myocardial infarction (relative risk 2.1). Those who exercised fewer than 4 times per week had a relative risk of 6.9, whereas the relative risk was just 1.3 for those who exercised 4 times or more per week (p < 0.01). Mittleman and associates found that 4.4% of patients who had experienced myocardial infarction had been involved in heavy exertion. The relative risk (compared with little or no exertion) was 5.9. Again, regular exercise was shown to greatly attenuate the risk.

There’ve been many studies linked here on MFP in the past, suggesting benefits from regular high-intensity exercise (usually in interval form, such as HIIT), finding that it can have various benefits. This study seems like a useful, practical counter-balance in the sense that it underscores the idea that intensity is something to build up to, not undertake straight off as a beginner (or maybe even as an intermediate), if one wants to reduce one’s risk of adverse CV health events.

I don't think it supports the conclusion that high intensity is always and universally damaging. Conditioning is really important.