What's the best cardio workout?

Woman doing one of the best cardio workouts: skipping rope
(Image credit: Getty)

The best cardio workout will be one that gets your heart rate up but more importantly, it will be an exercise that you enjoy and can fit into your training program. Some of the most common cardiovascular exercises include hiking, running — either outside or on the best treadmills (opens in new tab) — cycling, swimming, HIIT (high intensity interval training) and rowing.

“Cardiovascular, or aerobic exercise, can be described as any exercise that gets your heart pumping. However, as most exercise does this, we need to look at the term ‘aerobic’, which basically means with oxygen,” explains sports scientist Jamal Ramsay.

Aerobic exercise refers to any activity where your body is relying on oxygen to help with its energy supply. This is opposed to anaerobic exercise, where your body doesn't use oxygen and instead draws on stored glucose to provide quick bursts of energy. 

Both types of exercise have their pros and cons, but usually when people say 'cardio workout' they mean aerobic exercise. Read on to find out more about different cardio workouts and which are best for calorie burn, muscle building and enjoyment.

Jamal Ramsay
Jamal Ramsay

Jamal Ramsay spent five years advising women on their health and nutrition at BUPA, a private health care provider in the UK, before co-founding women’s health startup jrny (opens in new tab). He has a background in sports science and is passionate about nutritional health and wellness.  

Which cardio workout is best for calorie burn?

HIIT training is probably the best option for calorie burn. It has a high energy expenditure and it depletes the oxygen available to the muscles, forcing the body to burn fat to get more energy to function. This puts the body in an oxygen debt so you will continue to burn calories even after your workout has finished, a process known as the After Burn Effect. 

A study published in the Journal of Strength and Conditioning Research (opens in new tab) found that a HIIT session on an exercise machine burned more calories than running, cycling and a resistance training session in a group of nine men.  

Woman doing hiit workout at home

(Image credit: Getty)

But even studies like the above won’t be able to account for all factors when it comes to calorie burn. HIIT regimes may burn more calories than other sports because it requires a lot of force and it engages large muscle groups. However, its repetitive impact can cause joint pain, which means you might not be able to sustain it for very long. Regular cycling sessions or swimming may be a better option for some people.

If you’re focused on calorie burn, it may be helpful to track statistics on one of the best fitness trackers (opens in new tab), but remember that these only offer a general estimate and aren't always accurate. 

For any effective and sustainable weight loss, you also need to be in a calorie deficit (opens in new tab). While exercise can help you achieve this, you can’t out-run a bad diet.  

Which cardio workout is best for muscle building?

Ramsay says that cardio isn’t necessarily designed to build muscle. “To build muscle, you need to be working against resistance. With that said, swimming is good because it’s a combination of aerobic and resistance training because you’re working against the resistance of the water. Cycling is also good for building muscles in the lower body.” 

Remember, cardiovascular exercise doesn’t have to mean spending hours on the Stairmaster or running uphill. In fact long sessions of ‘steady state’ cardio (continuous, moderate effort) has been proven to increase the stress hormone cortisol and break down muscle, a study published in the journal Psychoneuroendocrinology (opens in new tab) found.

Woman swimming in pool

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Which cardio workout is most time efficient?

Without a doubt, HIIT wins in this category. “HIIT training can burn up to 1,000 calories in an hour so is usually considered a great workout. Also, because you can fit HIIT sessions into very short periods of time, it is very effective for those that don’t have a lot of time to dedicate to exercise,” Ramsay told Live Science.

Be aware that HIIT is very demanding, so newcomers to exercise may find it offputting. It’s also likely that a tough HIIT session will cause some muscle soreness, so you’ll need time to recover after a session. 

Which cardio workout is best for enjoyment?

The best cardio workouts don’t have to equal hours on a treadmill — there are plenty of fun ways to enjoy cardio and find an exercise that motivates you to stay consistent. 

“If you love to dance, incorporate some dancing into your cardio routine. If you love to swim, try and get to a pool or beach, if you’re lucky enough to live near one,” says Ramsay. 

A good playlist makes exercise more enjoyable, too. One study published in Journal List (opens in new tab) found that listening to music during a workout could increase motivation and effort, leading to improved sports performance. So music really can influence your workout. (opens in new tab)

Woman listening to music and working out

(Image credit: Getty)

And training with a friend or partner could increase motivation levels because we tend to gravitate towards the exercise behaviors of people around us, a study published in the Journal of Social Sciences (opens in new tab) found.

Ramsay says: ““There’s no point in going for a run if you hate running, or trying to commit to swimming when the nearest pool is two hours away, making it hard for you to stay consistent. Just try to choose a cardio activity that works for you.

“And if you’re doing anything that might involve repetitive impact, like running or tennis, then it’s imperative to incorporate resistance exercise into your routine to avoid risk of injury and to protect your joints.”

Maddy is a freelance journalist and Level 3 personal trainer specializing in fitness, health and wellbeing content. She has been a writer and editor for 22 years, and has worked for some of the UK's bestselling newspapers and women’s magazines, including Marie Claire, The Sunday Times and Women's Health. Maddy loves HIIT training and can often be found working out while her two young daughters do matching burpees or star jumps. As a massive foodie, she loves cooking and trying out new healthy recipes (especially ones with hidden vegetables so the kids eat them).