National government guidelines call for adults to get two hours and 30 minutes of aerobic activity — like a fast walk or bike ride — each week. The physical activity guidelines issued by the Centers for Disease Control and Prevention emphasize that exercise helps keep your body in shape. It’s especially important when you have arthritis.

Carrying around excess weight can place added stress on your joints. There are many different types of arthritis, such as rheumatoid arthritis, osteoarthritis, and psoriatic arthritis. While each develops differently, staying active has proven benefits for people with all types of arthritis. Exercise not only reduces pain, but improves flexibility too.

Exercise is a win-win for arthritis — provided that you do it. A study published in the journal Arthritis & Rheumatology found that very few people with arthritis get the recommended amount of exercise each week.

That’s understandable. It can be hard to lift weights or run on a treadmill when your joints are sore and stiff. If you’re struggling with exercise because of arthritis, try an exercise program that’s ideal for sore joints: a water workout.

There are many reasons why a water exercise program is a good choice if you have arthritis. Here are three good reasons:

  • Water is buoyant. It supports your body so there is less impact on your joints.
  • If you exercise in a heated pool, you’ll get the added benefit of warmth, which helps soothe sore joints.
  • Water creates natural resistance when you move your body through it, giving your muscles a good workout without the need for weights.

When it comes to exercising in water, you have a few different options. The most obvious form of water exercise is swimming laps, which is a great workout. If you can swim laps for a whole hour, you’ll burn more than 470 calories.

But don’t dive in on your first try expecting to do a marathon swim. Start with just one or two laps, and gradually build up your endurance. Rest in between laps to restore your energy.

Another option is to take a water aerobics class at your local gym, YMCA, or senior center. Exercising with a group is motivating and will give you the chance to socialize.

Many gyms now offer water exercise classes, including aquatic versions of yoga, Zumba, tai chi, and Pilates. If you’re just getting started, choose something basic like yoga or tai chi. If you’re an expert exerciser, you can take a higher intensity water aerobics class.

Some water exercise programs were created just for people with arthritis. The Arthritis Foundation and other organizations offer special aquatic classes taught by certified instructors, which you can take a few times a week. The advantage to these programs is that they’re designed for all fitness levels, and they include exercises that are perfectly suited to people with sore joints.

Walking is great exercise, but when you do it in the water, it puts almost no impact on your joints. Because water exerts 12 times more resistance than air, walking in water will give you an even better workout than walking on land.

To walk in water, use the same technique you do on the street — heel to toe. To increase the intensity, hold light weights. If you’re going to walk in deep water, put on a flotation belt for safety.

Many people with arthritis find warm water soothing to their joints, but you don’t want the water to be too hot. A temperature of 83°F (28°C) to 88°F (31°C) is just right for exercise: It’s comfortable, without making you sweat too much.

If you’re exercising or sitting in a hot tub, make sure the temperature isn’t any higher than 104°F (40°C). And get out of the water after 10 to 15 minutes.

Before starting any new water workout, ask your doctor if it’s safe for you. Also, ask if you should avoid any specific exercises or movements.

At the beginning of a workout, start with a few easy stretches after a light 5- to 10-minute walk to warm up your body. Move through each movement completely but gently so you don’t put stress on your joints.

If any exercise hurts, or if you feel dizzy or out of breath, stop exercising right away.