Or a run, gym class, cooking seminar—any hobby or interest that you and your partner can do together, suggests Dr. Millheiser. "This can strengthen your emotional connection, and feelings of support boost desire." In one study published in the Journal of Personality and Social Psychology, couples that engaged in new and exciting activities had greater satisfaction in their relationships. "New and exciting" is all relative, so depending on how adventurous you are, that could mean anything from trying out mountain biking to skydiving.RELATED: 21 Signs You've Found Your Fitness Swole Mate
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Treadmill, schmeadmill. Why coop yourself up? Head out into the fresh air and hike yourself slim, toning your legs and butt in the process. No need to spend the entire weekend wandering through the woods, either-just one hour of hiking torches more than 400 calories. Here's what you need to know before you go.

Pick a Trail
Find one near you at Be sure to factor in more time when tackling steep terrain-hiking uphill takes about twice as long. To stay safe, bring a friend.

Gear Up
Trade in your sneaks for a lightweight yet sturdy trail shoe, like Merrell Siren Sync ($90; need those thick rubber soles that grip the ground to help prevent nasty spills and guard feet against sharp roots and jagged rocks.

Other essentials: water, light snack (like granola), cell phone, ID, trail map, mini first-aid kit, hat, sunscreen, and a light jacket in case of rain or a drop in temp. A bonus pick: trekking poles (try They boost your burn by up to 40 percent by working your upper body and helping you move more quickly.

Help your Bod
Post hike, do a few minutes of down-dog (start in push-up position and press your body up into an inverted V) to loosen calves, hamstrings, hips, and shoulders, and help stay ache-free.