When people decide to “get healthy" and “lose weight" one of the first things they often do is go and join a gym.
Of course, for anyone currently not getting enough exercise, taking up any new regime will have a beneficial effect alongside a healthy diet.
However, there are other (more fun) ways of getting fit - and we've heard some nasty rumours about what's hiding in those mirrored studios...
The air is polluted (really)
A recent study into the air quality in gyms found that most left a lot to be desired. Researches from Holland and Portugal assessed the air pollutants at 11 gyms during peak hours, and found large amounts of dust, formaldehyde, and carbon dioxide.
Areas which held dedicated classes (like spin classes) were found to be the worst offenders.
Breathing in too much of these – carbon dioxide in particular – can result in fatigue, and can even contribute to asthma or breathing issues.
Researchers believed the pollutants came from poor ventilation, cleaning products, and high levels of carbon dioxide being expelled by inhabitants of the fume parlour gym. We hear the air outside is nice and clean…
The sun doesn’t shine indoors
Vitamin D is essential for helping our bodies absorb calcium and maintain healthy bones, and it’s also believed it can ward off depression, cancer and heart disease.
Despite this, somewhere between 40-75% of us are deficient. We can get some vitamin D from foods such as eggs, cheese and mushrooms – but spending time in the sun is the best known way to boost your levels.
Not only that, but multiple studies have shown that being outdoors can reduce stress and improve mood.
Of course, you should wear sun cream to prevent yourself from burning and reduce risk of skin disease.
Other users are trying to make you ill
A survey by Nuffield Health revealed that of 2,000 participants, one in five still went to the gym with a cold - risking passing it on to someone else.
Half of participants admitted to using other people's towels and bottles, and a third failed to wear socks, which risks athletes foot.
Almost three quarters also said they often found other people's sweat left on equipment.
A study for Men's Heath by Dr Derren Ready also revealed high levels of bacteria in gyms - with 132 million bugs found in one area the size of a 2p piece in an unnamed London facility.
You could start only going to the gym at bizarre hours when no one else is there. Alternatively, you could save yourself both time and money, and just go for a bike ride instead...
Of course, any exercise is good exercise - we've got an in-depth look at the pros and cons of both cycling and the gym here.
If you do decide to forgo the gym, check out these great pieces of fitness equipment you can keep and use in your (clean) home!