Usually my muscles give up during exercise, however i want to know whether it is caused by lack of energy or muscle damage, Is there a way to know what causes our muscles to give up during exercise? Is there a way to know if it is simply your running out of energy or it is caused by muscle damage like DOMS because you don't feel soreness right after exercise?

  • Fyi, the d in doms stand for 'delayed'. Doms is what mostly beginners feel 1-2 days after training and has nothing to do with what you are describing. I don't have time to answer your question, but try googling 'muscle failure' or 'muscle fatigue'. You will find many excellent articles. Chances are any answer given here will be half as good as what you find on google
    – Raditz_35
    Nov 15 '19 at 17:03
  • I know that it stands for 'delayed', however my point is that during Doms muscle damage happens but you don't feel any soreness after exercise for about 24-72hours, how do i know the cause of why my muscles gave up, how do i know whether it was because of muscle damage or lack of energy?
    – Zheer
    Nov 15 '19 at 18:28

You have to define "give up".

  • If you mean giving up because of a weight that is too heavy, it's because your muscles don't have the capacity to create a contraction strong enough to overcome the weight you are trying to move.

  • If you mean giving up because at some point you can't move the weight anymore that you were moving a few seconds ago, I believe you have to distinguish two cases :

    • A heavy weight case. In this case, I believe you are giving up because your muscles can't create a strong enough contraction to move that heavy weight. I don't know exactly how this works. Maybe it's linked to the fact that you are mainly using fast twitch for heavy weight and fast twitch rely on ATP stores that get quickly depleted and thereby they can't contract anymore.
    • A moderate/low weight case. In this case, your muscles can't contract anymore because you are entering the same issue as above or because your muscles become "asphyxiated". That would happen in the case where your slow twitch muscles are working and you did so much work that you started producing acidic compounds through the non-oxygen metabolic pathway. At some point, those compounds prevent the muscles from contracting and therefore you can't move the weight anymore. This is the "burning sensation" that you might have already felt.

DOMS is only relevant after exercise not during. youd know if you had DOMS;for instance, DOMS in your quads can make you walk like someone spent the night practicing kickboxing your legs and almost hurts like stretching a very tight muscle.. having DOMS is painful enough to where you probably arent going to workout that muscle in your next workout without some tiger balm or something.

to answer your question.. if youre not having a medical issue or condition causing this, then it could be one of the below:

diet:do you get enough nutrients, protein, carbs, etc to. fuel your workout?

workout plan isnt good->either youre overtraining, training on a workout plan thay was made for someone more advanced, not resting enough between muscle groups or workouts, not resting enough between sets, using too many reps which will cause lactic acid build up causing you to fatigue.

training to failure: the common workout advice is to train to fail, or make it where your muscle barely finishes the last rep on each set before failing. the downside to this is doing it early on your first couple sets will drastically fatigue you, making you not be able to finish your last set or fatigue you.

muscular endurance-> you might have weak muscular endurance.. you can workout in 12 to 15 or 15 to 20 rep schemes to build endurance whicb will cause your muacles to not fatigue as fast. you can also do century sets(read up on this) to build blood capillaries to flush your muscles and recover quicker.

  • Does too many reps with very light or light weight cause lactic acid build up?
    – Zheer
    Nov 16 '19 at 9:47
  • yes. typically its impossible to move heavier weight for that many reps in order to cause build up as the average range is 20 to 30 reps, but can also be caused when your doing an exercise from 50 to 70 seconds time under tension, or doing circuit training alternating body parts for many reps. its not always a strict number, your body will let you know when youve done so many reps you get a burning sensation that forces you to quit. if your using extremely light weight, then its possible to avoid acid build up as your muscle isnt getting enough work
    – Ace Cabbie
    Nov 18 '19 at 3:23

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.