Sure, you’ve heard about the three set rule and know not to let your knees go past your toes when doing squats. But is there any truth to these oft-spoken words of wisdom? Let’s get to the bottom of these muscle myths.

The Twelve Rep Rule

Many weight training programs involve twelve repetitions per set in order to increase muscle mass. However, this may not be the best course for everyone. The number of repetitions you do should depend on your personal strength and fitness goals.

If your goal is to bulk up, doing a standard twelve repetitions may not provide enough resistance to increase muscle mass. What you really need to be focused on is how much weight you’re using. Using heavier weights and working until exhaustion offers the type of muscle growth that builds larger muscles, leading to a maximum gain in strength. If, however, you’re looking to build strength without adding muscle mass, use lower weights and perform more repetitions per set.

The Three Set Rule

Again, there is nothing set in stone that says you have to do three sets of each exercise. Again, you should base your workout on your particular needs and goals, not on any outdated rule. If your goal is to build muscle, you need to work the muscles until the point of failure – regardless of how many sets you need to achieve this. If your goal is just to build strength, work the muscles until you feel a good burn using as many sets as you need.

Three to Four Exercises Per Group

Many experts say to do three to four separate exercises per muscle group. While this may work for some people, it may prevent others from reaching their goals. If you are working your muscles to exhaustion as part of a bodybuilding program, you may only need one exercise per muscle group to achieve your goals. Anything further may increase the strain on your muscles, leading to injury.

One way to assess your current fitness plan is to be mentally present during and after your workouts. Do you have one muscle group that is sorer than the others? The muscle may be weaker than others, requiring additional exercises, or you may need to check and correct your form. Did you push one set of muscles hard, but feel fine the next day? If you’re working to the point of failure, you should expect some soreness the next day as your muscles heal. If you don’t feel that, you may need to add another exercise to really strengthen the muscles.

My Knees, My Toes

We can probably all remember past gym teachers warning us about the dangers of extending our knees past our toes when lifting weights. But is there any truth to this?

In 2003, researchers at Memphis University found that the real culprit was leaning forward during squats. In fact, they established that stress on the knees was nearly 30 percent higher when the knees extended beyond the toes while leaning too far forward doing squats. Hip stress also increased, as did strain on the lower back.

When doing squats and lunges, try to focus more on keeping your torso upright and not leaned forward. During squats, try to squeeze your shoulder blades together to help keep your chest lifted and the strain off your lower back. Doing so helps to reduce the stress on your back and hips.

If you really want to increase your strength and muscle mass, possibly the best thing you can do for yourself is to find a coach or personal trainer to oversee your fitness program. He or she will be able to recommend the best exercises for your goals and can help correct your form, preventing injury.