Could someone explain?

discretekim

i am having trouble finding the info in looking for on the Internet. I've been doing Zumba for a few weeks now. I've noticed this. From about ten minutes in to about thirty I am exhausted and feel like I can't do it. Then something changes and I have pretty good energy through the end of class. This never happened to me when I was a runner. But I think it has something to do with the kind of fuel your body is accessing during exercise. Like the switch to glycogen or something. I'm having trouble locating the exact info. Could someone explain this phenomenon?

hbrittingham

I have no idea, but it happens to me when I run. The first mile is hell, but then I get into it and it's not so bad. Then I hit mile 3 and suddenly feel like I could run for another 3 with no problem (though I don't actually run that far, I am at about 3-5 miles when I run).

discretekim

Interesting. Well I hope someone on here who is more well versed in the science will comment. I hate when Google fails me lol.

markiend

In non scientific terms, I have always know it to be called "getting your second wind"

Alidecker

I am like that when I swim. The first couple laps feel awesome, then I want to quit, then I finally find a rhythm and the swim feels a whole lot better.

jaga13

markiend wrote: »

In non scientific terms, I have always know it to be called "getting your second wind"

I agree

itsMcKay

Same for me. I think it's psychological. For me, anyway, it is. I can be at the gym, on the bike, bottle of water ready to go and think to myself, "Meh. I should just go home." How ridiculous is that?! Then the first 15 or 20 minutes, I'm having to force myself to stay and finish the workout. I do 30-minute sets on the stationary bike at 150 bpm heart rate. Sometimes when my 30 is up, I feel so good, I do another 30! But I'll be damned if those first 20 minutes don't feel like absolute torture. haha

Jruzer

This is pretty common with cardiovascular exercise. Based on vague past knowledge, I think this is due to the fact that it takes your body a while to get into a fully aerobic state. When you start exercising you are mostly using anaerobic systems to supply your energy and burning up glycogen. This works well for about a minute or two. As you continue to exercise your heart and lungs start working harder and harder to supply oxygen so that you can use stored fat in addition to the glycogen. But it can take several minutes for you to get fully in the aerobic state, so you struggle a bit as the transition happens.

I welcome correction from someone more knowledgeable.

https://runneracademy.com/aerobic-vs-anaerobic/
http://runneracademy.com/first-2-miles-the-worst-miles/

bkupron

If I had to guess, it would be acid build up in the muscles with exercise. It takes a while for your body to dilate all the blood vessels to effectively start removing the "poison" and your muscles feel oxygen starved. With anything, this gets worse if you are out of shape and the older you get. With me being fat and old now, I feel like collapsing in a heap after 1/4 mile. http://www.scientificamerican.com/article/why-does-lactic-acid-buil/

beemerphile1

Research endorphins.

garayjoh

Its an oxygen issue, The body has to adjust to satisfy the contracting muscles, once everything syncs, the body falls into the groove.

JoRocka

It happens- you gotta get like "warmed up" to it. When I first start running I think I'm gonna absolutely die and I'll be thrilled if I make it a single mile. And then once I get through that first omg I'm going to die... then I'm fine and I can manage for a while.

pretty normal.

SonyaCele

runners high. endorphins.

ladderguy

How long is the Zumba class, and how much time do you have to workout? A significant warm-up at a lower intensity for 15-20 minutes will alleviate this. The warm-up allows your heart, respiration, and cardiovascular adaptation to take effect without significant lethargy. Lactic acid has little to do with this. The effect of lactate occurs when you enter anaerobic metabolism and causes the burn you feel in the muscle, but the duration of this effect is very short once you reduce effort and return to aerobic metabolism( by short I mean minutes). The Scientific American review linked above is a nice summery of how this works. Endorphin release is variable for each individual and can occur at ten minutes or take as long as 60. This may have some impact on the sensation you are experiencing as well. There is no sure way of facilitating endorphin release(no reliable human studies), but it is generally accepted that High intensity exercise does speed up the release.
Anecdotally I have found is a 20 minute warm-up, with a 2-5 minute High intensity period early in the warm=up works best for me. Doing this my lethargy stopped occurring.