When you work out to failure you’re working a muscle (or muscles) to complete exhaustion. Doing so forces your body to come back stronger or more efficient. There are a lot of different ways to approach it, and without getting too technical or diving into specific training intensity percentages such as 60%, 70% 80% max, etc., it all centers around the concept of progressive overload. Quite simply: when you progressively overload your muscles, they adapt to what you challenged it with, and as a result, they should be able to do/handle more after recovering. If you’re bailing out of an exercise too early, it’s going to be a lot harder to see progress.
However, here are the caveats of failure training:
Training to failure all the time can be risky. Any time you’re challenging your body and muscles to their limit, there are breaking points. Everyone is different and might perceive failure at different times. Some people can naturally push until they are completely fatigued, others might want to stop at the first minor instance of discomfort. A good rule of thumb to follow when training to failure is to always maintain good form; once your form breaks down and you start recruiting other muscles or “cheating”, you’ve probably pushed too far past failure. This is when you can get hurt.
As far as how much to train to failure, this also varies from person to person. When it comes to strength training, if your joints start to ache or you’re completely exhausted everyday, chances are you’ve trained to failure for too long and it’s best to back off. You can train sub-maximally, but still try to do a little bit more with each week so you’re still progressing or continuing to progressively overload your muscles and body.
You could do sub-maximal or lower intensity workouts every other day, or go hard and heavy for a couple weeks, then go lighter and easier for a couple weeks, etc. But, for the most part, training to failure is without a doubt the fastest way to get results.
You’ve probably heard “if it doesn’t challenge you, it doesn’t change you.” That’s pretty much spot on.
By the way, the #1 reason fail to hit their fitness goals is eating wrong. Check out our piece on intuitive eating for lean muscle.
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