1. Yoga mats
Many gyms have signs reminding people to wipe down spinning bikes, treadmills, or weight machines after using them, and most gym users oblige. But this is not the case with yoga mats. They are notorious for spreading germs, viruses, and bacteria. In 2017, David A. Greuner, a vascular surgeon in New York, warned that dirty yoga mats can even carry herpes.
2. Strength-training equipment
If you knew how dirty free weights and weight-lifting machines really were, you would probably skip your strength-training workout. Weights, for example, have 362 times more bacteria than a toilet seat, according to a study by FitRated.com, a fitness equipment review site.
3. Swimming pool
Swimming is a low-impact cardio exercise many people prefer over sweating for an hour on a treadmill or a bike. Most pools are filled with disinfectants like chlorine to clean contaminants like sweat, skin lotion, and urine. But pool waters are still 2.4 times more likely to contain gene-altering agents than tap water, according to a study published in the Environmental Science & Technology Journal. (Hot tubs in spas are four times more mutagenic.)
4. Cardio machine screens and handles
Cardio machines — treadmills, bikes, ellipticals — are among the most used in gyms. For the amount of use they get, it’s not surprising that, by the end of the day, they are also among the dirtiest pieces of equipment at gyms. Liquid spills are inevitable. Add the constant contact with sweaty body parts and you have a long list of germs, some of which may be harmful. The average treadmill has 74 times more bacteria than a public bathroom faucet, according to FitRated.com.
5. Exercise balls
Exercise balls, also called stability, fitness, or medicine balls, are a very popular item at the gym. But they are also rife with germs that can lead to colds and other infections. A 2016 study of gyms in Ohio took 288 samples from various spots in gyms to test for one strain of staph bacteria, S. aureus, which can be resistant to antibiotics. Medicine balls were the most common surfaces to carry it.