We’ve all been there. You could have sustained an injury, or work’s piling up, or you’re simply not feeling up to digging into your usual exercise routine. And with inactivity comes anxiety—how long do you have before you start losing out on your hard-earned results? The good news is that if you’re generally fit to begin with, it’ll take much longer to notice the effects than if you’re an average person. However, we all lose out eventually. Keeping in mind that all individuals’ bodies are different, we’ve drawn together projections for fitness loss based on men with generally good fitness habits.
How long does it take before…
… Your aerobic capacity decreases
Within two weeks of putting off aerobic exercise such as running and cycling, the number of mitochondria in your body—your body’s energy plants on a cellular level—starts dropping. Your maximum oxygen level consumption also takes a dip. What that means is your body has less fuel, and less ways to turn it into energy.
After about two months of not exercising, you’ll lose roughly 25 per cent of your aerobic capacity, and after three months off, you may stand to lose up to half of it even if you’re a very fit athlete. On the other hand, a fledgling fitness buff who has been working out for two months may lose all their gains in the same amount of time. Regaining aerobic fitness is that much harder to regain than it is to lose it. Even if you only take two weeks off and experience minimal losses in your overall endurance, you’ll have to train another two to eight weeks before you’re back where you left off.
… Your muscles start getting weaker and losing power
Decreases in your overall muscle strength don’t occur quite as fast as dips in your aerobic performance do. For example, if you cut a consistent, thrice-weekly weight lifting routine down to a single day of fairly intense training every week, you’ll stop gaining strength, but you won’t exactly lose it, either.
If you do stop entirely, you’ll lose mass at the most significant rate somewhere around the seven to 10 day mark, after which your losses will taper off—which is not to say that they won’t continue. The average guy will see a moderate dip in strength after about 84 days. Bearing in mind that their maximum strength is far higher, well-conditioned athletes tend to get relatively weaker in a shorter period of about two to four weeks. The good news is that, to a certain degree, it will take you less time to recover from your losses than it did to build up your strength originally.
… You start regaining lost fat
For those exercising for fat loss, stopping a regimen dead in its tracks will inevitably result in regaining weight that was lost. This can happen for a several reasons, revisiting bad habits included. Most commonly, however, it’s because individuals continue eating the same amount of calories after they quit as when they were active.
One pound of fat equates to about 3,500 calories, unburned. If a typical person who exercises three times a week, burning 500 calories every session, continues ingesting those calories after quitting regular activity, he can expect to gain three pounds back within seven weeks. The only way to maintain his current body weight is by cutting them out.