Muscle is more metabolically active than fat, which means the more you have, the faster your metabolism is and the more calories you burn all day long—all key for a whittled middle. Resistance training builds this quality lean muscle, so do two to three total-body strength sessions a week, says Tom Holland, exercise physiologist and author of Beat the Gym: Personal Trainer Secrets Without the Personal Trainer Price Tag. For fat-melting cardio, all you need to do is your weight, he adds: If you’re 145 pounds, do 145 minutes a week, broken up however fits into your schedule—say, 60 minutes Saturday, 45 Tuesday, and 40 Thursday.

Let’s face it — slogging away on the treadmill or the weight bench can be boring. Making gym time a social activity is a great way to make any workout fly by. Ask a friend to join you for a gym date, book a session with a personal trainer, or join a fitness-minded group or meetup to socialize and exercise at the same time.

Do it Today: Work out with a buddy, a personal trainer, or a fitness group at the gym to stay accountable and active. 

EXERCISE CHEAT SHEET — THE HOW-TO'S
1a. Jump Lunge
Targets: Legs
How to: Take the traditional lunge up a notch. Start with a basic front lunge — but on the way up, explode with enough force to jump a few inches off the ground. Land softly with both legs bent at 90 degrees (and the front knee positioned directly over the ankle). Got the hang of things? Switch legs in mid-air, landing with the other leg in front. Alternate for 10-15 reps on each leg while maintaining a strong core and upright torso.

1b. Clapping Push-Up
Targets: Chest, triceps, core
How to: Ready to get a little hang time? This move starts with a standard push-up, but on the way up, push off of the floor explosively enough that the upper body takes flight. Bring the hands together mid-air for a single clap (or more if you’ve got it like that!), then return to starting position. Aim for 10-15 reps, or however many you can execute with good form.

1c. Single-Leg Glute Bridge
Targets: Glutes, hamstrings, lower back
How to: Start lying on your back with your knees bent and feet flat on the floor, about eight inches from your butt. Bring the right leg into the chest, then raise up into a half bridge position by pushing firmly into the left foot. Repeat for 10-15 reps, then repeat on the other leg. Not challenging enough? Try pulsing at the top (meaning dropping down a quarter rep, then back up a quarter rep before lowering all the way back down).

1d. Side Plank Star
Targets: Obliques, glutes, shoulders
How to: Got those side planks down pat? Time to raise the bar. Starting in a traditional side plank (forearm on the ground and body stiff as a board), lift the top leg straight up while keeping the rest of the body perfectly still. Hold it there for 1-2 seconds, then bring the top leg back down to meet the other leg. For those feeling nice n’ steady, try lifting that leg a few inches higher with each rep. Repeat for 10-15 reps, then switch.

2a. Handstand Push-Up
Targets: Shoulders, chest, core, glutes
How to: To play things safe, Angelilli recommends starting with the basic handstand. Spread those fingers wide, shoulder-width on the ground, about 12 to 18 inches from a sturdy wall. With hands flat like pancakes and pointer fingers parallel to each other, walk the feet as close to the hands as possible, so you’re in a short downward facing dog position. Next, bend one leg, and use it to kick the straight leg up and over your head until it hits the wall. (Be sure to keep those elbows locked!) Once you have the strength and balance to hold steady for two minutes straight, try out sets of 10 mini reps (lowering down 1-2 inches and returning to the starting point) with the feet riding the wall. Once your strength is there, try the full-on handstand push-up — we recommend a spotter for those first few attempts!

2b. Rotating Jump Squat
Targets: Legs, core
How to: The basic bodyweight squat gets some serious hang time with this advanced move. Lower into a traditional squat, back flat with thighs parallel to the ground, and explode off the ground, rotating mid-air 180 degrees counterclockwise. Land softly in a squat, and with no rest in between reps, launch into the next jump, rotating 180 degrees clockwise this time. Be sure to keep the chest up and spine long, using your breath and your abs to help power you through. Repeat for 10-15 reps.

2c. Plank Balance
Targets: Core, shoulders, hip flexors
How to: Starting in a traditional plank position with the back flat and forearms planted securely on the floor, simultaneously lift your left arm and right leg until they are parallel to the ground. Hold for a second (or longer!), then switch, keeping the core tight and hips steady. Aim for 10-30 reps, or, go for time. (Any chance you can sing the Star Spangled Banner while holding tight?)

2d. Pulsing Superman
Targets: Lower back, glutes, core
How to: Ready to channel your inner superhero? Lie on your stomach with the arms and legs pointing to the back wall. Peel your upper body off the mat, and lift the arms and legs, keeping them straight. Next, comes the tricky part: At the very top of the position, pulse the body one inch up then one in down for 10-20 reps. Up the ante even more by making those reps super-slow — just don’t forget to breathe!

Want more? Check out 17 Powerful Bodyweight Exercises for Strength and Speed, or for a more beginner-friendly workout: The 30-Minute, No-Gym Bodyweight Workout.

Boost your burn: Using hand weights, resistance bands, or props like small balls while performing exercises can really amp up your calorie burn. Resistance of any sort makes your heart work harder, exactly the way it would when you sprint during a typical jog.
One of the best ways to increase your calorie burn on the bike is to use intervals that are constantly changing in both timing and type (hills, sprints, etc.) from ride to ride. For example, if you've been doing typical Tabata drills (20 seconds of work, followed by 10 seconds of rest), try 40 seconds of all-out, breathless effort followed by 20 seconds of recovery, for 6 rounds. In between intervals, work on climbing powerfully at a moderate to hard intensity. You'll definitely get the most out of your workouts.
Power Walking...Moving at a brisk pace on a firm surface burns about 350 calories an hour, but according to Matthews, there are various ways to boost your burn while walking! She recommends picking up the pace (ramping up from 4.0 to 4.5mph burns an extra 93 calories an hour), or walking slower on an incline (walking uphill at 3.5mph for one hour burns about 72 calories more than walking on a flat surface). Adding resistance can also help you torchmore calories with every step. Try wearing a weighted vest (a vest is preferable to holding dumbbells or wearing ankle or wrist weights which can stress the joints) or using Nordic walking poles,

To up the ante on their sweat quotient, exercisers can choose to take their workout to a hotbox. Some gyms now offer 80-100 degree versions of popular group fitness classes, from hot Pilates and hot Barre, to slightly steamier versions of indoor cycling classes, and TRX (suspension and bodyweight exercises taken from Navy SEAL training).

Over three decades ago, Bikram Choudhury had the hot idea to practice yoga in higher temps. Now there are over 600 Bikram studios in the U.S. alone. For the 90-minute class, an instructor runs through a series of postures performed in intense heat (105 degrees) and 40 percent humidity. That’s on the low end of what a sauna feels like. Note: We don’t suggest fully disrobing in a hot class simply because itfeels like a sauna.

Not all hot workouts are technically “hot.” Mimi Benz, president and founder of The Sweat Shoppe (an indoor cycling studio in North Hollywood) offers warm spin classes, where temps never rise above 82 degrees. Still too sticky? The difference, Benz says, is the safety risks of training in these temps are relatively low compared to environments above 90 degrees. In a 75-90 degree environment, as the body’s internal temperature rises, the heart beats about 10 beats per minute fasterthan normal. Higher than 90 degrees — the heart beats even faster.

Taking a workout to a hotter place can change the way the heart pumps. “Your heart has to work harder for blood to pump to the working muscles,” says Dr. Santiago Lorenzo, an Olympic decathlete and post-doctoral fellow at the Institute for Exercise and Environmental Medicine [1].

To regulate body temperature, the body sweats more in high heat, and consequently loses nutrients and minerals. “Sweating promotes detoxification and elimination through the skin, which is the body's largest eliminating organ,” Benz says [2]. But other experts believe the main function of sweating is simply to cool down, and extra sweat may impair natural detox function by the liver and kidneys. Since we don’t often choose to be locked up in an armpit of a room, our bodies are forced to adapt. “An external load like excessive heat can definitely be dangerous to an unconditioned individual as it increases the stress to beyond a level that they’re prepared to handle,” says Greatist Expert Kelvin Gary. 

IN THE HOT SEAT — THE ANSWER/DEBATE
 Studies show that there may be some negatives to heating up. Elevated temps may make heat-sensitive medical conditions worse, and increase risk for heat injury, which can range from mild cramps to a life-threatening heat stroke [3]. Heat exhaustion — which includes symptoms such as nausea, vomiting, headache, dizziness, weakness, and fainting — is more likely to occur as core temperature rises, says Greatist Expert Robynn Europe.

While heat may add a level of risk to exercise, it may also offer some benefits (though research is somewhat limited). In one study, elite cyclists who hit a chilled space after acclimating to a 104-degree lab, showed improvements in performance by 4-8 percent [4]. The study’s head researcher, Dr. Santiago Lorenzo believes working out in high heat can be safe because of peoples’ ability to adapt to elevated temperatures[5]. But, he cautions to stay hydrated (see specific recommendations below), andlisten to your body. If the heat becomes unbearable, Lorenzo says to slow the pace, cool down, and stretch.

Confinement to a hot room may not be for everyone. People with high blood pressure should take caution before heading for the heat, and same goes for pregnant women (whose internal temps should not exceed 102 degrees).

A final word of caution: Since some of these studies examine only elite athletes, researchers can’t promise the same adaptation ability for recreational exercisers. With plenty of variables to consider — fitness level, hydration status, exercise intensity, and length of exposure to the heat, more studies are needed to know how effective it can be as a training method. Moral of the story: Try it out, but bring a sweatband anddrink plenty of water beforehand. The key to staying hydrated: Drink frequently and early, before you have a chance to feel thirsty during exercise. The American Council on Exercise recommends consuming fluids at regular intervals throughout the day, and sipping 17-20 ounces of water at least two hours before any hot class.

As far as gear goes, wear lightweight, breathable clothing so the body can properly cool down, and hit the scale before and after a workout. A weight loss of two percent of your total body weight or greater can be a sign of dehydration (that’s three pounds for a 150-pound person). And if you tend to get dizzy in the hot stuff (baby, this evening), or dehydrated quickly, check with your doc before trying that first hot sesh.