Which “expert” should you listen to for advice on how to get and stay in shape? We culled this crowded field and zeroed in on four top fitness bloggers, each with his/her own exercise philosophy and hacks. Here are their secrets to…

LOSE WEIGHT…AND KEEP IT OFF

Jen Widerstrom is the undefeated fitness trainer who helped two seasons of contestants on NBC’s The Biggest Loser. She is also the fitness director of Shape magazine and author of the best seller Diet Right for Your Personality Type. She encourages “physical literacy” and believes that health benefits will naturally accrue by just increasing how much you move around during daily activities. An app featuring her workout program, WiderSTRONG, is available at NEOU.

Favorite fitness tip: Strong-man training—such as sled-pushing, rope-pulling and throwing medicine balls. This type of training builds muscle but doesn’t stress joints, which is crucial if you’re carrying around extra weight.

RECLAIM YOUR BODY AFTER CHILDBIRTH OR MENOPAUSE

Kathy Smith, best-selling author and creator of hundreds of exercise videos, is now in her late 60s and still living what she preaches. Her approach to fitness is about progress, not perfection—getting healthier and stronger is relative and something that everyone can achieve. For example, women in their 30s and 40s may be looking to get their pre-pregnancy bodies back…while women entering or already in menopause may want to focus on keeping joints flexible and improving balance and posture.

Favorite fitness tip: The Plank pose is a favorite because you can achieve substantial benefits—including toning your upper body, butt, legs and inner thighs—in a short period of time. Do the Plank every morning. Start by holding the pose for 15 seconds and gradually build up to two minutes. Remember to actively engage every muscle down to your heels.

GET STRONGER

Cary Williams, a former Olympic-style boxer and winner of the Pacific Northwest Women’s Tournament, is currently an Olympic-level boxing coach with USA Boxing. She has trained many boxers, as well as boxing and weight-training instructors. She also regularly blogs and video-blogs on strategies to lose weight and get in shape.

Favorite fitness tip: It’s all about the core. She instructs her students that throwing a proper punch requires keeping the core engaged (i.e., abs contracted) to maximize power. You can do this at home without a punching bag or gloves. It’s called shadowboxing. You don’t actually hit anything, but you can get the same exercise benefits. When throwing each punch, remember to rotate your hips slightly and keep your abs engaged. Practice using both sides until you “feel the burn” in your abs! Start with doing it for 30 seconds and build up to one minute.

GET QUICKER RESULTS

Vince Sant is a Las Vegas–based fitness trainer and cofounder of V-Shred, a program that offers a series of workouts designed to help you meet your fitness goals quickly. Sant believes that there is no one-size-fits-all approach to getting in shape…and that achieving fitness doesn’t require hours at the gym. Most of his workouts are high-intensity interval training (HIIT)—short, intense bursts of exercise that target all of the key muscle groups with rests in between. His 10-minute HIIT workouts burn more calories than a typical 45-minute cardio workout.

Favorite fitness tip: Superset (two exercises performed back-to-back) or circuit (several exercises done back-to-back) exercises—because they allow you to do more in less time. They also elevate your heart rate more, which helps burn more calories. Example: 10 squat jumps followed by 20 seconds of tricep dips, 20 seconds of mountain climbers and then 15 bicep curls. Do four reps of the whole circuit without resting between exercises.