6 Reasons Your Gym is Toxic

No one goes to the gym intending to get sick. The gym is a place of wellness, fitness, and improved physicality. Or is it? Many people, attempting to reap the incredible benefits of exercise, sign up for a gym membership and spend hours each week locked inside a toxic environment, all in the name of health. 

Exercise is critical for health, and daily movement is the key to helping you achieve your 100 Year Heart. However, you might want to exercise somewhere other than the gym. Here’s why.

Toxins lurking in your gym

Volatile organic chemicals (VOCs) and allergens

You might be working out in the gym because you live in a city and want to get away from the polluted air. Unfortunately, your gym is likely even more toxic. The Environmental Protection Agency (EPA) estimates that indoor air pollutants are five times higher than outdoor air pollutants.

While this is certainly true in your home, it is even more of an issue at the gym. Hundreds of people pass through every day, bringing dust particles and heavily perfumed products and deodorant and fragranced, toxic laundry detergent — releasing VOCs into an enclosed, poorly ventilated space. 

A study by the University of Lisbon and Delft University of Technology in the Netherlands evaluated the air quality levels of 11 gyms during business hours. They found toxic VOC levels exceeding the national limit values, especially in enclosed gym rooms during fitness classes. The researchers also discovered significant amounts of potentially toxic airborne dust.

Volatile organic compounds (VOCs) like formaldehyde can contribute to upper respiratory infections, cardiovascular disease, and cancer. VOCs can come in with gym customers or cleaning products used to keep the equipment germ-free (more on this later), paint, and exercise equipment and mats.

Excess carbon dioxide

The same study found high levels of carbon dioxide (CO2) in Lisbon gyms. High CO2 levels mean there is insufficient oxygen in the air. This is common in gyms since exercise increases respiration and CO2 expulsion. This results in a crowded gym of people working out and breathing in carbon dioxide instead of oxygen.

Many gyms have inefficient HVAC filters and pump recycled air through their ventilation system. Enclosed rooms in the gym allow this toxic air to build up, and it has no way to dissipate quickly. After all, when was the last time you went to a gym that had open windows for air circulation? Likely never. 

Excess carbon dioxide inhalation is connected to fatigue, asthma, rapid heart rate, and breathing issues. Not exactly what you want to experience when you’re trying to get your workout on. 

No sunshine 

While this isn’t an issue strictly related to the gym, it is a considerable concern with the rise in the popularity of indoor workouts. Our bodies need regular sunshine exposure to boost vitamin D levels. Even if you work out next to a window in the gym, the glass blocks UVB rays that allow you to synthesize vitamin D. 

Though vitamin D supplementation is an acceptable way to make up for weak sunlight in the winter, there is no replacement for the sun’s power. Vitamin D is critical for proper heart function, bone health, neurological protection, and immune system regulation. 

The best way to get your daily dose of sunshine is by working out outdoors. You are exposed to harmful pollutants and robbed of the sun’s healing power when you stay inside. Exercising outdoors is linked to decreased stress, improved mood, better health, and deeper concentration. 

Cleaning products

There is nothing wrong with a clean gym. Most of us would agree that we would rather use sanitized equipment than equipment coated in sweat. However, in the quest for a sterile environment (especially in the age of Covid-19), many gyms use chemical-laden cleaning products.

Not only do these cleaning products release toxic VOCs (see above), they can also wreak havoc on your hormones. Many cleaning solutions used to disinfect gym machines are endocrine disruptors known as quaternary disinfectants. These chemicals interfere with estrogen and testosterone production and can even impact your liver, thyroid, and kidney function. 

Quaternary ammonium compounds could also contribute to lung sensitivities and even cause new asthma cases. 


Phenols, another common chemical in cleaning wipes and sprays, can cause skin irritation, muscle weakness, and cancer after long-term exposure. 

Germs and illness

Remember those toxic disinfectants? Unfortunately, they are not only dangerous for your health, but they’re not even used effectively in most cases. 

Gyms often encourage users to clean their equipment, but many people skip this step, and even if they do wipe down the weight bench, it is usually a single halfhearted swipe. Even if the equipment is wiped down, most disinfectant products need to sit on a surface for a few minutes to sanitize properly. 

Plus, many people go to the gym when they are sick, exposing others to potentially harmful illnesses and bacteria.

Methicillin-resistant Staphylococcus aureus (MRSA) infections are particularly problematic in gyms, as the antibacterial resistant superbugs love hanging out in athletic facilities, saunas, and locker rooms. These high-touch areas can cause illness and infection to spread like wildfire, especially when proper cleaning protocols are not followed.

One 2014 study found Staph bacteria on every piece of gym equipment tested in four gyms. They took samples from weight machines, treadmills, free weights, and ellipticals and found 25 different kinds of potentially harmful bacteria. That doesn’t exactly instill confidence in the cleaning procedures of fitness facilities. 

Toxic gym culture

Though many gyms are places of positivity and encouragement, others tend to exude a toxic fitness culture that creates an environment of judgment and exclusivity. If you feel out of place in the gym or don’t want to go work out because you compare your fitness level or your body type to other people, get out! 

Everyone is worthy of getting in shape and if your excitement for working out is dampened by going to the gym, find another place to exercise. Grab a supportive friend and get outdoors together. The social interaction and accountability will help you enjoy your exercise and stay consistent.

What to do instead

Just because the gym is toxic doesn’t mean you should stop pursuing your fitness goals. You can often get a better, healthier workout at home or outdoors. Plus, you’ll save money on that pricey gym membership.

Instead of hitting the toxic gym, support your fitness goals, have fun, and protect your heart with these great outdoor exercises. Whatever you do, just get moving for at least 30 minutes each day. 

  • Go for a walk or a jog
  • Do yoga or tai chi outdoors
  • Use battling ropes staked in your yard
  • Swing a kettlebell or use dumbbells outside
  • Go for a bike ride
  • Plan a day hike

Try this full-body outdoor workout to help you quit the gym for good:

  • 10 minutes of walking or jogging to help you warm-up

Bodyweight circuit:

  • 20 squats 
  • 30-second plank
  • 20 jumping jacks
  • 30-second right-side plank
  • 20 lunges
  • 30-second left-side plank 
  • 15 push-ups

Repeat circuit two times with 10 minutes of walking or jogging in between. 

Remember to stretch!

Next steps

Unlike restaurants, hospitals, and grocery stores, gyms are not subject to health inspections. Many gyms fall slack on cleaning procedures and create environments for bacteria, illness, and toxins to thrive. Exercise safe and smart by staying outside.

Eat Well · Live Well · Think Well 


Medical Review 2022: Dr. Lauren Lattanza NMD

In order to live well, one must eat well.

Get the Natural Heart Doctor approved Diet and discover how to eat for your 100 Year Heart.

Work With Us

Discover how we can help you achieve your 100 Year Heart.

NHD Patient Application Form

SUBSCRIBE TO THE NATURAL HEART DOCTOR NEWSLETTER

Join our community by subscribing to the free, Natural Heart Doctor Newsletter. You'll receive great natural health news delivered right to your inbox.
Join 30,000+ subscribers.
It’s completely free.