Help me understand heart rate.

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  • juliewatkin
    juliewatkin Posts: 764 Member
    Do other people find that their heart rate is higher when they first wake up than doing regular stuff during the day? My typical heart rate during the day is mid to high 50s but is much higher when I first wake up. I guess I don't find waking up restful. My body has a fight or flight reaction.
  • tycho_mx
    tycho_mx Posts: 426 Member
    Glycogen in the liver is not easily accessible. In the first twenty minutes, you burn the glycogen in the blood stream. Beyond that, your body is using fat for fuel. If the scientific community has come up with a new study, I am not aware of it.

    There have been many studies on glycogen depletion. If we burned only fat for fuel after 20 minutes, there would not be the infamous "wall" in the marathon. I am an ultramarathoner who has been running for over 35 years, and I have seen a lot of change; but research results on glycogen depletion have been pretty consistent. The focus of research now is how to get your body to burn fat sooner.

    I'm not an ultra marathoner. I only run the little 26.2 marathons. Only have 24 under my belt.

    Deplete the body of carbs and fat will be the source of fuel. It takes time and training to get to this point. Replace sports drinks with water and Nuun or salt tablets, and you'll be fine. Run slow and avoid the lactate threshold and you'll never see the Wall.

    I'll never win a marathon as long as I win.

    But I'll never come in last.

    *wink*

    Not quite right. Fuel source depends on intensity at a large amount. And sure, you can exercise at a slow rate and use mostly fat as your fuel. As exercise intensity increases, mobilization of free fatty acids in plasma decreases but total fat acid oxidation increases simply because you're working out harder :)

    http://www.gssiweb.org/Article/sse-59-fat-metabolism-during-exercise-new-concepts

    That doesn't mean you burn more fat overall, because exercising at higher intensities is more time-efficient. In other words, you can burn 2000 calories in 5 hours or in 2.5.

    If you're eating at a reasonable deficit, you will still get overall less body fat. But you only get faster by doing some high intensity workouts as well.

    I'm not a runner - cyclists tend to compete at a large range of durations and intensities (from 20 minute time trials to 6 hour road races) so we tend to specialize less than runners.

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