There is a group of people who, every year around this time, end up in either my office, or the orthopedist’s office. They are “weekend warriors.” These are the people who, in spite of doing no physical activity all fall, winter, and spring, run outdoors to play softball like they did in high school or try to jog five miles the moment the sun peeks out or they get a whiff of summer air. Perhaps you can guess the common results: injury, overexertion, chest pain, and a baffled realization that perhaps we aren’t all as young as we once were.

Before you tie up your sneakers, we need to have a little talk about this, because while exercise is crucial for good heart health and having active fun outdoors is certainly a good idea theoretically, it is fundamentally not in your best interest to go from zero to hero. You might pull or tear a valuable body part, or uncover in the most unpleasant of ways a lurking heart issue. You may feel like a warrior out there on the beach volleyball court, but if you haven’t been in training, you are waging a war on yourself.

You’ve heard the saying “Use it or lose it.” Children get physical fitness as a gift, but the older you get, the more you have to earn it. Unless you work on it regularly and practice, you will lose it. Aging is a perpetual war against physical entropy.

As we get older, the body naturally has a decrease in its aerobic performance, because there is a decrease in oxygen intake, and a decrease in the heart’s ability to pump blood. A well-conditioned athlete can stay in shape and continue to exercise, but it gets more difficult with age. Studies show that muscle strength peaks at 25 years old, plateaus at 35 to 40, and by 65 years old, there is a 25 percent loss of peak muscle strength. The body has to work harder to swing that ball, kick that ball or run up that hill, so be kind to it. Don’t expect it to do what you want, just because the weather is better. Pay attention to it, and know that you might just have to start slow.

The good news is that physical exercise is a perpetual war against aging! However, when starting to exercise, it is critical to get your body back into shape, and reteach it what to do. The best way to do this is to monitor your heart rate when you exercise. Many gym machines have heart rate monitors on them, or you can buy a heart rate monitor and strap it on before you exercise. You will be able to read your rate on a watch,. Here’s how to find what yours should be:

1. Subtract your age from 220 for a maximum heart rate. For example, if you are 40 years old, your maximum heart rate is 180 beats per minute, or bpm.
2. If you are just beginning to exercise again after a long winter (or a few long winters!), begin training at 65 percent of your target heart rate. In our example, that would give us a rate of 117 bpm, which is 65 percent of 180.
3. As you get in better shape, gradually work to achieve a higher heart rate, until you are working at 85 percent of your maximum. In our example, this would be 153 bpm. When you can sustain this for a 30 minute exercise session, you are officially back in shape.

If you don’t have a heart rate monitor, then try your initial exercise with a friend. Try to talk, but see if you can get to a stage where you can finish a sentence, but have a bit of trouble completing it. That’s where you start, and that’s your beginning place for getting yourself in shape.

It’s human nature to “spring clean.” We want to feel fresh and new, to let the summer sun inspire us to move and exercise, but pushing yourself too far is not worth the risk. Check with your doctor before you jump into the fierce competition of your local soccer league or that totally inspiring new Zoomba class at the gym. Know your risk factors for heart disease before you stress your heart and ease your joints and muscles back into action.

So go ahead — break out the shorts and sundresses and bathing suits all at once, but get fit safely so you don’t end up sidelined. It is worth it! Exercise can do so much for your health, for your heart, for your spirit. As I always say, “Exercise is the best medication,” but like any medication, you should take only as directed.

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