When done right, exercise can help you to live life on your own. But follow the wrong advice and you can easily set yourself up for injury. Take the sit-up: Once considered the gold standard of core exercises, we now know that it can make low-back pain worse when performed incorrectly.

Unfortunately, a lot of these misconceptions stem from the ever-so-present “fitness influencers” who share tips based on anecdote and gym lore. “Once those opinions are disseminated to the public and take hold,” says Brad Schoenfeld, a professor of exercise science at Lehman College in New York, “they are hard to change.”

Below are a few of the myths that trainers from around the country wish could be debunked:

Myth 1: You should stretch before you work out.

If you’ve taken a high school gym class, you’ve probably been told to spend a few minutes stretching before exercising. But recent research has found that stretching before exercising is ineffective for preventing injury and may actually work against you. Just holding a stretch doesn’t replicate the motions and activity that you will be doing, and doesn’t start to get the muscles working ahead of your exercise.  In addition, stretching a muscle for more than 90 seconds actually temporarily diminishes its strength. According to Dr. Josh Goldman, associate director of the Center for Sports Medicine at UCLA Health, if you stretch before working out, “You’ve just transiently weakened all the muscle groups you’re trying to train.” Save your stretching for a separate time, he said. “I like to tell people to do it before bed,” since it gives your muscles time to recover before moving again.

So for the most effective preparation to work out, professionals recommend a dynamic warm-up—performing gentle repetitive motions in a way that gradually increases motion, circulation, and muscle length. This will be more time efficient and productive overall. For more information about dynamic stretching see your 2023 blog Isn’t Warming Up Before Exercise Just More Exercise? We suggest doing foam rolling, shorter or active stretches, and some corrective exercises targeted specifically to you! If you’re not sure what’s right for you, ask our trainers.

Myth 2: Walking is enough to keep you fit as you age.

Walking is popular among older Americans for good reason: It’s been shown to lower the risk of heart disease, diabetes and certain cancers, as well as the risk of premature death. And it’s so doable. But walking on its own is not enough to stay fit as you get older, said Anne Brady, an associate professor of exercise science at the University of North Carolina-Greensboro. Starting in your 30s, your muscle mass progressively declines, she said, so you also need to focus on strength training.

“People can do daily activities with a minimal amount of cardiovascular fitness,” she said. “But when they don’t have the strength or the muscle power to do daily activities, that’s when they lose their independence.” Complement walks with at least two 20-minute strength-training sessions every week.

Myth 3: Heavy weights bulk females up.

Some people, particularly women, are concerned that adding strength training will build muscle bulk to the point they will look like a bodybuilder. This is not true. For a female to bulk up, she would have to do a lot of strength training — and I mean a lot. Women do not have enough testosterone to bulk up the way men do. Competitive female bodybuilders follow strenuous diet and workout programs that likely feature use of various muscle-building supplements. See our May 2024 blog Strength Training For Women for more information.

Myth 4: Running destroys your knees.

Research has debunked the notion that running increases your risk of osteoarthritis, and even suggests it can protect your knees against the condition. In fact, not moving increases your risk of developing osteoarthritis, along with age, weight, and genetics.

For years, experts thought that “our knees were like tires — you drive the car a lot, you burn through your tire tread,” Dr. Goldman said. “That is not true, because our body is dynamic,” and our joints can regenerate themselves, especially when we are regularly active.

That said, running can definitely lead to knee pain or injury if you train too aggressively, said Dr. Jordan Metzl, a sports medicine physician at the Hospital for Special Surgery in New York. Dr. Metzl called this “violating the rule of toos” — running too fast or too far too soon. “Increase slowly,” he said. And if you start to feel knee pain, get it checked out as soon as possible by a sports medicine expert.

Myth 5: You need 10,000 steps a day to be healthy.

An entire industry has been built on the claim that 10,000 steps a day are necessary to be healthy. The completely arbitrary number has not only become entrenched in popular culture as the gold standard, but it has sold many step-counting devices and inspired interoffice competitions. So where did this number come from? We explain this in our 2021 blog post Why 10,000 Steps? Simply, the myth traces back to the 1960s, when a Japanese clock manufacturer mass-produced a pedometer with a name that translated to “10,000-steps meter” in an effort to capitalize on the Tokyo Olympics.

The latest research suggests that the health benefits of walking appear to plateau at around 7,500 steps, but even as few as 4,000 steps per day can reduce the risk of dying from any cause.

Myth 6: No pain, no gain.

While feeling uncomfortable during a workout is normal, feeling pain is not. Many athletes live by the "no pain, no gain" motto, but pain is the way your body tells you that something is wrong. If you start to feel pain during a workout, stop immediately. If you continue to push through it, you could end up with a serious injury.

Myth 7: Muscle confusion.

Muscle confusion is a marketing term used to describe changing up your workout frequently in order to prevent your body from hitting a plateau. In some cases the workout changes on a weekly or bi-weekly basis, but there is no truth that switching up your workout regularly is "tricking" your body. Much of this myth is attributed to trendy workouts claiming that by changing up your workout routine, your muscles will need to continue to adapt to prevent complacency. This banks on the fact that people are struggling with cycling through the same routines, with the same weight, with the same intensity. 

In reality, it's the load that muscles adapt to. So, if you aren't practicing progressive overload in your training, then your body will continue to adapt. This includes increasing the weight you're lifting, increasing the number of reps or sets, or changing up the tempo or time under tension.

Myth 8: Fasted cardio for weight loss.

Fasted cardio, or exercising on an empty stomach, has been part of the great debate when it comes to weight loss. It gained popularity when bodybuilder Bill Phillips put it on the map in his book, Body for Life. The idea behind doing fasted cardio is that you'll burn more fat because your body is using stored fat as energy instead of glucose.

Although you may initially burn more calories by doing fasted cardio, ultimately it doesn't make a huge difference when it comes to weight loss because what matters most is your total daily calorie intake. In other words, if weight loss is your goal, being in a caloric deficit is far more important than whether you exercise fasted or not.

Myth 9: Exercising to burn off food.

If you follow fitness accounts on social media, you've probably seen those infographics that tell you the workout equivalent to burning off a chocolate bar or a certain type of food. While in theory this sounds like it would make sense, the truth is you can't out-exercise your food choices. Keep in mind everyone's body varies when it comes to how they burn calories, because it depends on factors such as your weight, lean muscle mass and your activities, and studies have found that even the time of day can affect how many calories we burn. So it would be hard to even pinpoint how long you would have to work out to burn off a chocolate bar. 

Myth 10: You can’t get stronger as you age

Although our strength declines as we age, strength training can absolutely combat the effects of this! You will get stronger if you are training with intention. It can be difficult to know what to do, how hard to push, and what form to keep so you can safely exercise at any age - which is why we suggest hiring a trainer to help you reach your goals (we’re biased, but our members agree).

If you’d like to know if something is a fitness myth, ask a certified Success Studio personal trainer by asking in the comments below.