In one of the fitness classes I was teaching the other day, the topic of conversation turned to how exercise has evolved over the last 40-plus years. I graduated from Central College in the late ’70s and for someone to go to a gym to exercise or attend a fitness class was not common at all. One of my good friends would actually get up before classes and run. Really? I hadn’t seen my first treadmill, and Richard Simmons wasn’t even “Sweating to the Oldies” yet.

Exercise has definitely made a statement since then and it is here to stay. Through the years, exercise research has become more and more extensive, and the fitness industry has grown into BIG business. As it has evolved, so have some myths throughout the years. Let's look at some of them.

“I am doing 150 crunches a day and I can’t get rid of my roll around my middle!” To build your core muscles, crunches, sit-ups, and other ab exercises are what you need to do. Before your abs will show, though, you have to have a good diet along with performing those exercises

“I don’t feel any pain so I better work harder.” Pain is not a threshold you need to cross when exercising but a warning sign to stop or slow down. Alice Burron, a former bodybuilder and spokeswoman for the American Council of Exercise, says you should not be exercising at a level of pain — ever. You may feel some soreness the next day or two after working out, especially if it was a new activity for you. Any pain or discomfort during exercise should be noted and you could check with a doctor if it continues.

“How did I injure myself? I always stretch before I exercise.” An 8- to 10-minute warm-up of some light cardio — walking, pedaling on a stationary bicycle or step-ups — is important to increase your blood flow to your muscles, which gets them ready for whatever exercise you are going to do, according to researchers at the U.S. Centers for Disease Control and Prevention. Same thing at the end of your work-out: do some light cardio and then stretch out the muscles.

“I’m hoping to turn this fat into muscle by lifting weights.” Sorry, but muscle and fat are two different types of tissue. You can burn fat while building muscle and you can lose muscle mass and gain fat, but you can never turn one into the other. Wouldn’t that be nice if we could?!

“If you’re not sweating, you should pump up your intensity.” Sweating is not a measure of exertion, but is a way for your body to cool down. There are, however, several types of exercises that do not cause you to sweat and are very good for you — walking, yoga, light strength training, or even working in the garden. Remember that any exercise is better than none. If you are doing some hard cardio activity, you should be working up a sweat. If you are not, you better step it up.

Be aware of these myths and other statements or activities that seem too good to be true. As I have said many times, do what makes you feel good, listen to your body, find a time that you can commit to exercise, and mix up your workout. These are all facts, not myths, that you should live by.

Julie Kirk is a fitness instructor at Great River Health Fitness. Her column appears in Currents the second Friday of each month.