Heading to the gym may also be a better option for those who need extra motivation to make their workout happen. One study found that people who work out with a partner are generally more motivated than solo exercisers.
In addition to the social environment offered at gyms, experts say that group workouts led by a certified instructor also ensure participants get a safe and effective workout, learn proper cues, and stay accountable—there's no skipping those hellish burpees you usually "forget" to do. Plus, you can continually try new, innovative workouts that you may not be able to do on your own.
And let's face it, gyms have advantages no study needs to prove. Those hot, steamy showers, saunas, pools, and even spas can make any exercise experience feel a lot more luxe.
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The Best of Both Worlds
In the end, you don't have to choose just one. Some workout groups exist entirely outdoors, while lots of gyms offer seasonal classes outside.
As the line between indoor and outdoor exercise continues to blur, what's becoming clear is that mixing up indoor and outdoor sessions is a great way to keep exercise exciting and, most importantly, fun.