For most of us, hopping aboard the fitness wagon is tough enough, while remaining on board seems almost impossible at times.

But once we establish a regular exercise routine which suits our needs and goals, the vast majority of us wonder how we ever survived without multiple sweat-sessions a week.

Considering how difficult it to get started, it's no real surprise that the vast majority of us fear gaps in our routine – created by holidays, work responsibilities or injury –  and often question whether our hard work will go to nought if we can't stick to our regime.

And unfortunately, the answer to that question is yes… for a time, at least.

According to a recent study, it takes a lousy two weeks for our bodies to lose muscle mass if we don't train regularly, and 14 days without exercise can also increase the risk of heart disease and diabetes too.

Researchers at the University of Liverpool enlisted the help of 28 individuals aged 25 – none of whom were fitness fanatics, but who walked at least 10,000 steps a day, were defined as 'moderate to vigorous activity', and boasted a 'healthy BMI'.

By reducing their physical activity by 80 per cent or more (dropping from around 2 hours 41 minutes a day to only 36 minutes), the participants – after two weeks – gained fat, specifically around the stomach area, lost muscle, saw an increase in cholesterol levels and couldn't run as fast.

But thankfully, before you go cancelling your fortnight abroad, this can be reversed pretty quickly.

"The effects were entirely reversible – so it’s fine if you’re fit and well and you go on holiday for two weeks and then you get right back to normal," assured the study's co-author Dan Cuthebertson.

"But the problem is that many people don’t reverse back to these levels of activity, and then perhaps the effects will accumulate. The longer people are inactive, the harder it is to get back into shape," he asserted.

So, while the results sound pretty disheartening, reversing them is totally within your power!