2 . It comes as no surprise that exercise is good for your health. Positive changes happen to your body before, during, and after a workout.     1    

Build up your body

There are quite a few scientific reasons to do strength training. It makes muscles (肌肉) bigger and bones stronger, thus lowering the risk for certain diseases. Running is an easy but effective way to help build your muscles.     2     But a recent study found that a short run can benefit the legs in the short term. And for now, experts say running has more benefits than risks.

Improve your brainpower

Exercise can help your brain, not just your body. Physical activity helps brain cells (细胞) grow.     3     That’s because physical exercise quickly increases a person's heart rate and carries more blood to the brain, improving the brainpower.

Establish a mind-body connection

Too much stress can lead to inflammation (炎症).    4     But simple mind-body exercises like yoga can not only reduce inflammation but also lower the risk of depression. New research shows they can even change your genes to fight off poor health. Research proves that even just 15 minutes a day of practicing mindfulness seems to do the trick.

    5     National guidelines recommend more than two hours of physical activity each week. But science says people who pack that amount into one or two days get about the same benefits. Either way, get moving is the key!

3 . Why do you run? Different people have different reasons. Whatever your reason is, there’s one thing we can be sure of: Running is much better injury-free. In his book, Dr. Jordan Metzl’s Running Strong, Metzl has the perfect suggestions for enjoying your running without losing your well-being (健康). Here are five must-follow rules for injury-free running:

Train for your level of fitness and your goals.

Don’t run more miles than your body can deal with. If you run for fitness and your goal is about 30 minutes a day, that’s cool. But if you are just starting out,     1    

Wear the right shoes for your feet.

You will hear lots of opinions about whether running shoes really help prevent injury and whether you should even wear them.     2     And some of you may need a little added assistance from inserts (鞋垫).

    3    

Be honest about how much sleep you need and stick to it. The cool runner is the one who wins the race. Sleep will get you there.

Fuel (提供能量) your body right for running and recovery.

    4     And after a workout or race, you need to deliver nutrients to all the body rebuilders in your muscles, so they can do their job and get you back into tip-top shape for your run tomorrow.

Pay attention to pain.

When pain changes the way you run, stop running.     5     And use dynamic rest (动态休息) to stay in shape until you are back on your running feet.