How to Decide if Cycling or Swimming Is a Better Cardio Workout for You

Both swimming and cycling are effective, low-impact forms of cardio exercise. But if you needed to choose between swimming and cycling, is it better to pedal or paddle your way into better shape?

The good news is there's no bad choice. In a May 2017 British Journal of Sports Medicine study of more than 80,000 adults, those who swam reduced their risk of dying of heart disease by 41 percent and of any cause by 28 percent (over the course of the follow-up period). Meanwhile, cycling cut the odds of early death by 10 percent in an October 2014 International Journal of Behavioral Nutrition and Physical Activity study.

Ideally, you'd incorporate both cycling and swimming — among other activities — into a well-rounded workout routine. "Doing complementary forms of exercise benefits your physical and mental health," says Tom Holland, an exercise physiologist, triathlete and author of The 12-Week Triathlete. You'll challenge your body in different ways and keep your mind engaged, preventing boredom and burnout.

Whether either — or both — options fit into your life depends on everything from the equipment you have to the health of your muscles and joints. Here are some pros and cons to consider when comparing swimming and cycling.

Swimming necessitates a body of water, be it a pool, lake or ocean, which, depending on where you live, can be challenging to find. You'll also need the right apparel, and potentially extras like goggles, a swim cap, fins, buoys or kickboards.

Cycling is often much more convenient. Yes, it requires access to a bike. But once you've checked that off the list, you have many more options of where to ride, says Sharone Aharon, personal trainer, triathlon coach and founder of Well-Fit Triathlon & Training, Inc. in Chicago. You can pedal a trainer or stationary cycle at the gym or at home, or take to the road, path or trail nearly anywhere you live, work or travel.

Both swimming and cycling require a significant amount of energy. According to the Centers for Disease Control and Prevention, a 154-pound person burns about 295 calories cycling for 30 minutes at 10 miles per hour or faster. Meanwhile, the same exerciser torches 255 calories swimming slow, freestyle laps.

Submerging yourself in water supports about 90 percent of your body weight. That eases pressure on muscles, bones and joints and makes it easier for your heart to shuttle oxygen-rich blood to working muscles. This means your heart rate could be up to 17 beats per minute slower for any given effort level.

For this reason, how you feel when swimming is probably a better gauge of the cardio workout you're getting than the numbers you'd read on a heart rate monitor (not to mention, it's more challenging to find one that's waterproof). If you feel like you're working hard, you are, even if your heart rate stays on the low side.

Read more: Is Swim Training a Good Cardio Workout?

When it comes to skill, swimming demands more, Aharon says. You'll need an awareness of where your body is moving in space and the ability to maneuver your arms and legs through complex movement patterns. And then there's the issue of breath: Learning to control it with each stroke represents a significant challenge.

Cycling comes more naturally, and many people learned to do it as a child. Pedaling focuses your efforts more on large, strong muscles such as your quadriceps. "In biking, you can work the legs a lot harder than you can work any body part in swimming," says Aharon.

However, swimming represents a total-body workout, engaging your core, arms and shoulders as well as your legs, Aharon says. Because of that, you'll need less time in the water than on a bike to stimulate the same fitness-enhancing changes in your physiology, such as the growth of new blood vessels and energy-producing structures called mitochondria within your cells.

Read more: Swimming for Beginners: Read This Before You Dive In

Your shoulder is the most mobile joint in your body and the most susceptible to injury, Holland says. Over time, training in the pool can lead to tears, inflammation or other types of complaints in both your shoulders and your back. The risk increases significantly if you swim with poor form, Aharon adds.

"Biking is more forgiving," says Holland. "But you can still have tightness and muscular imbalances that develop over time."

And of course, cycling outside does come with the chance of a crash. If you have balance or vision problems, it's probably better to stick with swimming or indoor cycling. Taking a spin class or riding a stationary bike can get you many similar benefits without the odds of a traumatic fall. Check out these cycling tips before hopping on a bike.

In the end, both cycling and swimming have their perks. When deciding how to incorporate them, you should also consider the fun factor, Aharon says. If you enjoy a type of exercise, you're far more likely to stick with it, thereby increasing the benefits you'll reap from your routine.

Keep in mind, too, that swimming is just one type of water-based workout. You can also walk, run, cycle or dance in the shallow or deep end. This gives you even more options to find something you'll love in the long run.