Why You Should Think Twice Before Joining F45

F45 is an Australian-based gym that has expanded all over the world. Their unique class format promises a couple of things: you're going to sweat, and you're going to have fun.

"The 'F' stands for functional training, a mix of functional and HIIT-style workouts geared towards everyday movement," explains F45's YouTube ad. "45 is the total amount of time for sweat-dripping and heart-pumping fun. With thousands of exercises in our database and an almost infinite amount of combinations, our sessions are always fresh and innovative."

Unlike most gyms, the workout you'll do depends on the day. F45 features curated exercise routines focusing on cardio, resistance, and a mixture of both. While how many calories you'll burn doing an F45 workout will vary, it's safe to say that you'll sweat — a lot.

However, some people have given up F45 and similar gyms in favor of other options, like quick and easy at-home exercise routines. There may be more to a good workout than sweat and burned calories.

Experts say super intense exercise, like F45, may not be ideal for you long-term. A Swedish study found some concerning results regarding those who frequently undertake strenuous workouts. In the study, volunteers did HIIT workouts on cycles. For the first two weeks, they saw good results. However, researchers noticed a negative trend in the volunteers' mitochondria by week three. That meant they couldn't produce as much energy, along with a slew of other ramifications (via The New York Times).

Exercising too much or too intensely could produce the opposite of your desired results. According to Everyday Health, some risks of overtraining are low energy, decreased immune response, an increased resting heart rate, and even depression. In addition, it turns out that going overboard with exercise can cause you to produce too much cortisol, the stress hormone. Personal trainer Aaron Cook says that overtraining combined with daily stress and anxiety can be a bad mixture (via Stylist).

"The nature of HIIT is exactly what it says on the tin – it's high intensity," says Cook. "This, therefore, requires a certain response from our body. One of the many responses that our body goes through is a huge increase of cortisol, triggering our 'fight or flight' sympathetic nervous system."

The fight or flight response is good when it's appropriately active. However, it becomes a problem when it's engaged while you're supposed to be at rest. Such a state can cause mood changes, affect sleep, and make you anxious (via Healthline).

While F45 might be suitable for experienced athletes, it's probably not the best idea for beginners. Unfortunately, many weight loss hopefuls also fall prey to the F45 challenge, a meal plan that goes along with the workouts. The mix of calorie restrictions and intense training can be a recipe for injury and overtraining syndrome (via Studio Kinetic).

Should you cancel your F45 membership? Not necessarily. If you're a seasoned fitness enthusiast who knows how to care for your body and avoid overtraining, participating in F45 could be a rewarding experience. However, if you're looking for a simple way to exercise for the day to improve your health, there may be better options with substantially less risk.