When professional athletes come back from an injury, they may think they're as good as new. But impatience can backfire.

Take LeBron James. He was sidelined with a strained groin on Christmas Day 2018 as the Los Angeles Lakers played the Golden State Warriors. Although he came back a month later, he was reinjured in a Christmas 2019 contest. Then in April of 2020, James sat out another game — again for a sore groin.

Fortunately, most injuries don't sideline people permanently. You can even start or continue exercising if you have heart disease — and it can reduce your risk of premature death.

However, you should plan your routine with your doctor so the intensity of the exercise is safe for your condition.

To help you get back in the game, the European Society of Cardiology has issued new guidelines on exercise for people with heart disease and heart-threatening obesity and diabetes:

• Exercise so your heart and breathing rates increase, but you can talk comfortably. Aim for 150 minutes a week. Our tip: Increase intensity by no more than 10% weekly.

• If you suffer from obesity, high blood pressure, or diabetes, add strength-building exercises three times a week to a regular routine of moderate/vigorous aerobics.

"The chance of exercise triggering a cardiac arrest or heart attack is extremely low," says sports cardiologist Dr. Sanjay Sharma, chairman of the guidelines task force.

But if exercise causes palpitations, unusual shortness of breath, or chest discomfort, take it easy and see your doctor ASAP.