We talk to an exercise physiologist to see how inactivity can affect fitness over time, and what you can do to hold onto those hard-earned gains if you can’t commit to your usual workout routine.


There are always times in life when you won’t be able to train or exercise as often as you’d like, be it the off-season, injury, or just life in general. So we asked Carly Ryan from Exercise and Sports Science Australia how quickly we lose the fitness we’ve worked so hard to achieve.

But first, a few things to consider

Often referred to as deconditioning or detraining, how quickly you lose fitness depends on several factors, such as how fit you are to begin with, how frequently you generally work out and how long you’ve been out of action. A person with a higher level of fitness will experience deconditioning at a slower rate than someone who is relatively new to exercise.

And according to Carly, “we know that the less active you are, the quicker the loss. For example, people who are bed bound can see significant loss of muscle mass and cardiovascular fitness in just one week. If you are still active in your daily activities the loss will be slower. “

Age, gender, and the reason you’ve stopped exercising are also factors to consider. Meaning the effects of deconditioning due to inactivity will vary from person to person.

Read more: Setting recovery goals after injury

1 to 2 weeks for cardio loss

Your body’s ability to transport and utilise oxygen is one of the first things you’ll notice after a prolonged period of inactivity.

“It’s the first thing that starts to decline - you will likely feel a small difference after 1 week without exercise. After 2 weeks, there is significant loss”, says Carly.

2 to 3 weeks for strength loss

When it comes to maintaining your muscle strength, Carly says, “Muscle mass (the size of the muscle) decreases when there is no stimulus, and your muscles become less efficient. Some suggest you can lose up to 10% of strength in one week, and over three months you will lose most of your gains.”

However, with some limited movement and light exercise, you can take more time off without significant strength loss.

What’s the minimum requirement to maintain fitness?

According to Carly the good news is that, maintaining fitness requires less work than building it. So if you've had a bit of a break from exercise, don’t fret. In fact, it’s important to integrate rest periods in-between workouts in order to give your muscles enough time to recover and rebuild.

Carly’s advice? “Aim for 2 sessions of resistance training to maintain strength, and accumulate 150 minutes plus of moderate physical activity each week. Try to set aside some time for some exercise sessions - even one session is better than nothing.”

"Try and maximise the amount of active movement in your day - take the stairs (even run them if possible!), do some active gardening or cleaning, park further away from the shops, play in the park- you are only limited by your imagination to be active.”

Any activity is better than none, so whatever your reason for pressing pause on your routine, try to make up for it in other ways.

Read more: Why high intensity interval training is so good for you

And watch what you eat

Finally, if you’re sitting it out for a week or more, it’s important to embrace a holistic view of your fitness. What you eat is equally important during periods of inactivity, more so as your body’s caloric requirement will reduce with no exercise.

By all means treat yourself this holiday season, but always be mindful that you won’t be burning the fuel as fast as you used to when training regularly.

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