Why it made the list: There are many reasons to like leg raise variations, but one is their scalability. You can start doing bent knee raises in the Roman chair or ab straps to focus on the lower core, work up to straight leg raises, and then move to a hanging bar. By the time you can do full straight-leg toes-to-bar raises, your entire core will have strength for days.
To do it: Lie on your stomach with your upper body propped up on your elbows and a dumbbell upright on the floor about six inches in front of your chest. Tuck your toes under and lift your body into a full elbow plank, making a straight line from your head to your heels, drawing in your abdominals. To start the move, lift your right arm off the floor and use your best freestyle stroke to reach over and past the dumbbell—as far as you can—allowing your hips to rotate into the stroke and turning through the balls of your feet. Finish the full stroke before returning to elbow plank position. Repeat with the left arm. That's one rep. Do 10 reps total, alternating sides each time.
To make sure you stay safe, put one hand underneath the small of your back, crunch your head and shoulders up just a handful of inches, hold for about 10 seconds, and release back down, advises Stuart M. McGill, Ph.D., director of the spine biomechanics laboratory at the University of Waterloo. This move basically ensures that you aren’t rounding your back so that your weight doesn’t drop into your low spine, per McGill.
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."