Max Heart Rate diminishing with training?

[AlexK]

This topic may have come up in the past, but I couldn't find any related posts and decided to try starting a new thread.

I last rowed competitively more than 40 years ago, and have long since switched to paddling (marathon and sprint K1, and, after moving to Florida, surf ski and outrigger canoe racing). Recently turning 60 and noticing some loss of muscle mass (most likely due to age and a lot of endurance training on the water), I decided to supplement my routine with some weight training at the local gym, where I happened upon a C2 and was instantly hooked. Oh, the joy of discovering a previously unknown level of pain! Since then, while chiseling patiently at my rather unspectacular 500M and 2K times, I started to notice a funny thing: try as I might, I was unable to hit my max HR, which until then had been consistently in mid 170's. With an all-out effort in a 2K time trial, I was still hovering around 155 (although it felt more like 255!). I can still hit low 160's on the treadmill, where it doesn't feel nearly as agonizing as on the C2, but that's as high as I can push it. It just seems really odd: my overall fitness has improved and I've definitely lost some flab, but what's the deal with my HR max dropping almost 15 BPM in less than 6 months?

Wondering if anyone has had a similar experience, and, if so, is there an explanation?

Alex

[lindsayh]

I started to notice a funny thing: try as I might, I was unable to hit my max HR, which until then had been consistently in mid 170's. With an all-out effort in a 2K time trial, I was still hovering around 155 (although it felt more like 255!). I can still hit low 160's on the treadmill, where it doesn't feel nearly as agonizing as on the C2, but that's as high as I can push it. It just seems really odd: my overall fitness has improved and I've definitely lost some flab, but what's the deal with my HR max dropping almost 15 BPM in less than 6 months?
Wondering if anyone has had a similar experience, and, if so, is there an explanation?
Alex

The most likely explanation is that you haven't actually reached your MHR I guess. If you can still see in the 160s on the treadmill then that is closer. A 2km is probably not sufficient to reach your maximum. A hard 5km TT would be closer to the mark but the "standard" test short of getting into an exercise lab would be to set up 4'/1'r and repeat with an faster pace for each interval until you can't go on.

[Leo Young]

Alex,

Max HR is inversely proportional to the size of your heart, i.e. the larger your heart, the lower your max HR. So often, as you do more endurance training, not only will your HR be lower at any given workload, but your max HR may well decrease as well, due to an increase in stroke volume. However, as you age, there is also a generalized tendency for your max HR to decrease due to deterioration in the the electrical conductivity capability of the heart. This loss, however, may be largely minimized by consistent endurance training as you age. The more rested you are (especially your central nervous system), the easier it is to reach your true current max HR. Conversely being fatigued, or over-trained makes reaching your current max HR highly unlikely.

Furthermore your max HR varies for different exercise activities and is influenced by a number of factors, including:
1. The amount of muscle mass being employed, i.e., the greater the muscle mass used, the higher your max HR.
2. Postural position: Exercising in an upright/standing position (e.g. running, Skierg, Stand Up Board paddling) produces a higher max HR than activities where you are seated (e.g. rowing, cycling, kayaking), with the lowest max HR occurring in prone/supine activities (e.g. swimming, board paddling) due to the amount of work the heart has to do to facilitate venous blood return.
3. Specificity of endurance fitness for different activities: Being highly and efficiently trained for a specific activity, ensures peripheral conditioning factors (e.g. specific muscle/fibre capillarisation, aerobic enzymes and mitochondria) are not a limiting factor to central factors (cardio-pulmonary, i.e. heart/lung/blood factors) achieving maximal functional activity, prior to local/peripheral fatigue becoming the limiting factor.

[jamesg]

rather unspectacular 500M and 2K times, I started to notice a funny thing: try as I might, I was unable to hit my max HR,

These two facts, low HR and low speed, are directly connected.

The other sports you mention are mostly high rate trunk, shoulder and arm work. Rowing is the opposite, low rate legwork. So suggest you adjust your technique until you can pull 200W at rating 20 for say 10km. A year or so of this will give you the endurance to pull a fast 2k. The stroke is the same, but at 33-35 rather than 20.

[skiffrace]

but what's the deal with my HR max dropping almost 15 BPM in less than 6 months?

Your HR max has not dropped, and the treadmill is the proof.
Considering that rowing is at least as hard as running, the most likely reason is that your body has not *sport specific* adopted to rowing (yet).
This is somewhat akin to a novice trying a sport (any sport)
He will not likely be able to exhaust himself. There will be some limiting factor (lack of muscle strength, sub-maximal volume of pumped blood, shortness of breath etc. ) that will "stop" him from going all out.
Something similar happens with your body. You may be fit in general, but not very fit for rowing.
Chances are that with regular rowing you will be able to row at higher level of effort and HR max.

[AlexK]

Thanks for everyone's input, guys - especially the very informative post from Leo - it's a kick hearing all the way from Australia!

Will try to incorporate your suggestions, and continue making better friends with the erg!

Alex

[skiffrace]

it's a kick hearing all the way from Australia!

Man, the internets these days, way fast, not like back during Eisenhower administration

[AlexK]

it's a kick hearing all the way from Australia!

Man, the internets these days, way fast, not like back during Eisenhower administration

The "internets" today are not even like they were just a few years ago, when one could still post things online largely without the risk of stepping on yet another snotty troll

[skiffrace]

The "internets" today are not even like they were just a few years ago, when one could still post things online largely without the risk of stepping on yet another snotty troll

Becoming impressed by post "all the way from Australia" in the era when everybody is wired and data travels at ~40% of the speed of light (rough estimate of networking speed) indicates parochialism, technical ignorance, or both. Lack of sense of humor does not help either.