Do it: Lay face up on the floor with arms straight above your shoulders. To start, bring your knees directly over your hips and bend at the knee so that your calf forms a 90-degree angle with your thigh. Next, simultaneously lower your left arm above your head while straightening your right leg and sending it towards the floor. Pause, return to the starting position, and then repeat on the opposite side. Do 14 alternating reps to complete one set.
Eat carbs. "There's this notion that carbs are bad and that you need crazy amounts of protein to be lean and fit," says Alcantara, who disagrees, and eats just as much carbs as protein, although the ideal ratio varies based on your goals. "Whatever you eat to get the results you want has to be sustainable, otherwise you're going to end up right back where you started with the same habits that got you there."

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