They clock in wearing sports bras instead of pencil skirts. Peek in their supply closets and you'll see kettlebells and battle ropes instead of paper clips and spare pens. And in their world, toner has nothing to do with printers and everything to do with defined upper arms and shapely glutes.
Personal trainers have dedicated their professional lives to building better bodies. We called up some of the best in the biz and picked their brains for the slim-down, firm-up tricks of their trade.
1. You Can't Just Do Cardio
Walking, running, cycling, and other heart-pumping activities have a whole host of benefits—burning calories, boosting your mood, protecting your cardiovascular system. But when it comes to weight loss, you also need to head to the other part of the gym, where the barbells and dumbbells reside, says Michelle Blakely, a trainer at Blakely Fit in Chicago.
Like cardio, strength training burns calories while you're doing it, but lifting also comes with benefits that last far longer, Blakely says. The more muscle mass you have, the higher your resting metabolism, which means you'll burn more fat even when you're just sitting on the couch.
What's more, strong muscles promote good form during your run, hike, or spin class, protecting you from injury and helping you reap bigger benefits from your sweat sessions, says Allison Hagendorf, a certified health coach with the American Council on Exercise.
More from Prevention: 10 Best Strength-Training Moves For Women Over 50
2. Heavier Weights Net You Bigger Results
Functional body-weight moves like push-ups, squats, and lunges make everyday activities like lifting groceries or climbing stairs easier, Hagendorf says. Reaching for heavier dumbbells—those you can lift for only 8 to 15 reps—can stimulate the type of lean-mass production that truly transforms your body.
"For someone who has never done weights, they may find they have a better body in their 40s than they did in their 30s when they start strength training regularly," says Liz Neporent, a trainer and fitness expert in New York.
Don't fret about bulking up—unless you're spending hours at the gym and pounding down massive quantities of protein, it just won't happen. In fact, resistance training essentially "shrink-wraps" your body, tightening and firming you in all the right places, says Hagendorf. Your clothes will fit more loosely and you'll look slimmer, even before the number on the scale budges.
3. The Best Workout Won't Deliver Without Upgrades to Your Kitchen Routine
They may not use corporate-speak like "synergy" and "touching base offline," but trainers have their own sayings.
Among the most popular: "You can't out-train a bad diet," says Samantha Clayton, a former Olympic sprinter and personal trainer in Malibu, CA.
Your workout can complement your initial weight loss efforts and help maintain a new, slimmer physique. University of Alabama researchers recently studied women who lost 25 pounds. Those who did strength training and cardio three times per week offset the slowdown in metabolism that typically occurs after you shed pounds, staving off regain, according to the study published in Medicine & Science in Sports & Exercise.
However, you'll have to change your eating habits to see significant changes to your body in the first place.
"Even if you're doing everything right in the gym, if you aren't eating to optimize your training, you're never going to get the results you want," Hagendorf says.
Start with small changes—one less packet of sugar in your coffee, a side salad with your lunch. Keep that up for two weeks, and then pick two more minor adjustments. Eventually, you'll build a nutritious and sustainable diet, says Liz LeFrois, a personal trainer in New York and a fitness expert on the streaming fitness site Acacia TV.
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