If you're hitting the gym and eating healthier than ever, why aren't the pounds coming off? This kind of perpetual weight-loss plateau can be as mysterious as it is frustrating. But thanks to new research, there's hope.
Researchers found that there's a sizable group of people called "non-responders," whose bodies won't respond to a typical moderate-intensity exercise program, according to a new study by the American Council on Exercise (ACE). If you're a "non-responder," like 36 percent of people in the study, a "traditional" cardio and strength training exercise program most likely won't result in any changes to your bodily function. Translation? No weight loss for you.
So how do you escape the non-responder rut? It's easy: Switch up your workout. There were zero non-responders in another group that performed more functional and dynamic strength training movements. (Related: Here's when and how to switch up your workout routine.)
In the study, researchers monitored a control group (no exercise), a "standardized" exercise group (who did a traditional cardio and strength workout routine), and a third group that completed an Integrated Fitness Training (IFT) program (including cardio training as well as functional and resistance training). To monitor intensity, researchers had the standardized group exercise to a particular percentage of their maximum heart rate, and had the IFT group exercise to particular ventilatory thresholds (aka when your breathing rate suddenly ramps up to keep up with your workout).
Both exercise groups started the 13-week program with three weeks of cardio exercise only, increasing the intensity each time by hitting either a heart rate or ventilatory threshold target. Both groups exercised three times a week, increasing their cardio training from 25 min/day in the first week up to 50 min/day during weeks 9 through 13. For the final 10 weeks, the groups added functional and/or resistance training to their cardio workouts. The standardized group did a circuit of strength machines for 2 sets of 12 reps each, including:
- Bench press
- Shoulder press
- Seated row
- Biceps curl
- Seated leg press
The IFT group did a circuit with free weights and machines that allowed free motion, increasing the number of reps or amount of weight from week to week. Exercises included:
- Stability ball circuit (hip bridges, crunches, Russian twists, and planks)
- Kneeling/standing wood chops and hay balers
- Dumbbell squats to 90 degrees
- Standing one-arm cable row
- Step-ups with dumbbell onto a 15-cm step
- Modified (assisted) pull-ups
After completing the program, 36 percent of the standardized group had zero increase in VO2 max, so were dubbed non-responders—while 100 percent of the people in the IFT group showed an increase in this important fitness marker. Plus, the IFT group showed significantly more changes in body-fat percentage, blood pressure, balance, and muscular strength tests using a bench press and leg press.
The reason the IFT group saw much better results? Intensity. The traditional weight machine approach may underestimate intensity for some people, meaning, they won't hit the threshold needed to drive real results, according to Lance Dalleck, Ph.D., lead author of the study. Just think about it—most of those strength machines in the standardized workout are done while seated, which obv isn't going to get your body working as hard as dynamic movements like squats, pull-ups, step-ups, standing wood chops, and lunges, which were in the IFT group. (Here: more workout strategies to bust through that weight-loss plateau.)
The fitness world encourages people to "just get to the gym" and that "any kind of exercise is better than no exercise," which is partially true—moving your body is never a bad thing. But this study sheds light on why going to the gym and wasting hours on "meh" workouts might not actually be helping that much. You're better off turning up the intensity—whether it's with bodyweight Tabata workouts, functional fitness routines, or lifting free weights.