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You Asked: What Is Muscle Fatigue?

You're asking and I'm answering.

"Hey Fit. In a lot of your weight lifting posts you talk about picking a weight that leads to 'muscle fatigue or failure' but I'm not really sure I know what that means or how that feels. Can you explain it for a newbie?"
– Muscley Marianna

I'm guessing you're not alone in not really knowing what muscle fatigue is, so this is a great question. To see my answer just


The important thing to remember when it comes to strength training is that you must challenge your muscles with more weight than they can handle to make them stronger. This is where muscle fatigue and failure come into play. Have you ever felt some discomfort, a slight burning sensation, or even pain in the muscle you're working when doing resistance exercises? If so, then it sounds like you're probably experiencing muscle fatigue. When resistance training, you should try to reach a minor level of muscle fatigue with at least one set per exercise.

To really give your muscles a workout then you want them to reach failure (or momentary muscle failure). This is the point during your set where the targeted muscles reach complete exhaustion. When you experience muscle failure, you could not possibly do anymore repetitions without compromising your form and/or using other muscles — possibly the only thing in your life you ever wanted to fail at.

When I am picking a weight to start with for a new workout, I choose a weight I can only lift 15 or so times before really feeling fatigued. This means that after two or three sets, my muscles are going to be pretty well worked and I will have most likely worked through fatigue and achieved failure.


Join The Conversation
aimeeb aimeeb 9 years
Great explanation.
JaimeLeah526 JaimeLeah526 9 years
I love that feeling when you can't lift anymore.
rpenner rpenner 9 years
Best failure ever
julibul julibul 9 years
gabiushka gabiushka 9 years
I need to go back to my workout!!!! My mom is visiting for 3 weeks and its driving me crazy not going to the gym!!!!
Renees3 Renees3 9 years
I like strength training more than cardio. I love feeling strong and seeing my muscles!! My trainer just decided to start upping my weight because I've gotten stronger and the old weights we were using weren't enough. PHEW I was Sore after that workout! But it felt SO good
missbanana missbanana 9 years
i love my strength training. i feel like superwoman after
saradee saradee 9 years
isn't it funny how achieving failure can feel so darn good?
angelfromlsu angelfromlsu 9 years
I need to get heavier weights.
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