Nothing gives you an endorphin high quite like cardio [1]. Whether it's an exhilarating run, sweaty and fierce indoor cycling, or a fabulous dance class that makes you feel like your most confident self, getting your heart rate up is a surefire way to boost your mood — and burn a tremendous number of calories [2]. Through cardio, you'll also improve your (as you might have guessed) cardiovascular health [3], in addition to your overall endurance and stamina. It might even help you live longer [4]!
But . . . can you do it every day? Cardio — though gruelling at times — can become addicting, and it's common to see fanatics head to their favourite bootcamp or HIIT class every single day. While staying active and moving consistently is crucially important to your health, we wondered if there's a limit.
"It may surprise you that cardio is not recommended to do every day!" Jackie Cassado, Tier X personal trainer at Equinox [5], told POPSUGAR. Citing the CDC's recommendation of 150 minutes [6] of moderate cardio (read: NOT high intensity) per week, she said, "One of the best things you can add to your routine is the occasional day off [7]."
An excessive amount of cardio can actually put a strain on your body and increase the "fight or flight" response, because your body can't actually tell if you're running from a bear or tapping it back at SoulCycle [9]. This increase in physical stress can flood your body with stress hormones, which is taxing and exhausting — and can also lead to a decrease in lean muscle mass. "Doing the same amount of cardio every day can inhibit your recovery, causing you to lose muscle over time," Jackie said. Check out some effects of excess cardio that she outlined for us:
Negative Side Effects of Daily Cardio
- Increased appetite. "Traditional cardio may increase your appetite," said Jackie. "Ever finish a cardio workout and find you have a voracious appetite?" Um, yes. "Although more research is needed, there is some evidence that cardio triggers elevations in hormones that make you hungry, increasing appetite so that you eat more. This tends to make efforts to reduce body fat futile and may lead to disordered eating or excessive exercise when people find they aren't getting results."
- Fat gain. Jackie explained a phenomenon that results from excess cardio called "compensation," that occurs "when people exercise and then eat more calories as a reward," and noted that this can be a result of too much cardio. "They may also be less active in daily life, reducing the amount of energy burned daily. Compensators don't lose body fat from exercise and they tend to gain it." She cited a study [10] that showed "69 percent of women who did 30 minutes of cardio three times a week gained body fat due to compensation . . . some women increased body fat by 25 pounds." Yikes!
- Muscle loss. We detailed this a bit above, but she expanded saying that "over the long-term, doing cardio as your sole form of exercise leads to the loss of lean muscle mass."
- Slowed metabolism. "A decrease in lean muscle mass reduces the amount of calories burned by the body at rest and puts people at risk of pain, dysfunction, and increased diabetes risk," said Jackie.
- Inflammation and injuries. "Doing traditional cardio every day and not diversifying your workouts can also lead to inflammation of joints — and over time, injuries."
- Frustration. Jackie noted that from what she's seen with clients, excessive cardio can lead to frustration "because of the injuries or lack of results." Cardio "can also seem time consuming, and people eventually stop doing it" once they feel fed up.
Recommendations
You didn't think we'd just leave you here with all that bad news, did you? Now that you know what could happen, here's how to make sure it doesn't.
- Just take a rest day. 150 minutes a week means only five days a week, 30 minutes a day. Give yourself two days off when it comes to cardio [11]. Seriously, you WILL reach your goals when you do this.
- Brisk walks. "For people who are just beginning, I would recommend a brisk three-minute walk [12] either on a flat surface or a slight hill, and follow this with a rest for three-minutes," said Jackie. "Repeat this interval until 20 minutes or 30 minutes is reached."
- Do interval training. "For individuals who are active or athletes, I would recommend that you start with more intense running or cycling intervals," she said. "For example, a protocol that has been verified by research is 20 minutes of resisted cycling intervals of eight seconds interspersed with 12 seconds of rest [13], in which you cycle at a slow pace. The intervals are short, which makes the workout go by in no time." She emphasised that "the great thing about interval training is that it gives you all the traditional health benefits of cardio, but in much less time." And to boot, interval training can burn a lot of fat in a short amount of time — "traditional cardio" isn't as effective for that.
- Wingate protocol. Jackie described this form of interval training as something that "has produced significant fat loss in both men and women." It's a form of cardio where you "run all-out for 30 seconds and then do a passive recovery for three minutes." So this way you can get your cardio in, but still contribute to healthy fat loss.