Trainers love responders. These clients succeed immediately and continue month after month, losing weight, gaining strength, slicing off inches, normalizing hypertension, improving cholesterol levels, sleeping better and feeling better overall.
Then there are nonresponders. They hire trainers, have good intentions, train regularly and try as hard as they can to improve their health habits. But they do not lose much weight or fat, nor do they improve their muscle strength. They may feel better or sleep better, but they never seem to get the results they are looking for.
Frustrated nonresponders and their trainers need to understand that there may be a good reason for this lack of progress. It’s possible these clients have a genetic makeup that resists traditional exercise programs. Then the question is, if some people are natural-born nonresponders, is it even possible to turn them into responders? Multiple research studies suggest the answer is yes—especially if you add intensity, duration and resistance to their workouts.
Add Some Intensity to the Cardio
One way to help nonresponders is to increase the duration and/or intensity of the cardio training, according to one recent study.
Ross, de Lannoy & Stotz (2015) investigated whether exercise of different intensities and durations improved cardiovascular fitness (cardiorespiratory fitness was measured using a graded exercise test in which subjects walked on a treadmill). The study had 121 middle-aged (53.2 years) subjects (75 women, 46 men), all of whom were abdominally obese. Everybody completed at least 90% of the five weekly workouts over 24 weeks. Subjects were randomly assigned to one of three training protocols:
- low-amount, low-intensity training—30 minutes at 50% of peak VO2, designed to burn 180–300 calories per session
- high-amount, low-intensity training—60 minutes at 50% of peak VO2, designed to burn 360–600 calories per session
- high-amount, high-intensity—40 minutes at 75% of peak VO2 designed to burn 360–600 calories per session
After 24 weeks, the researchers tallied the nonresponders in each group. In the low-amount, low-intensity group, more than one-third (15 of 39) were nonresponders. In the high-amount, low-intensity group, the nonresponse rate declined to about one-sixth (9 of 51). Notably, the high-amount, high-intensity group had zero nonresponders.
The authors suggested that this study provides prescription options for trainers who work with beginning adult exercisers because it illustrates the results of adding quantity and intensity to workouts (see Tables 1 and 2 for more on programming for nonresponders).
Interval Training Also Works
Bacon et al. (2013) combined data from several studies to investigate the effectiveness of adding intervals to continuous exercise. The main finding was that interval training improves VO2max beyond the gains reported with continuous cardio training.
The meta-analysis, which evaluated studies that used interval training either alone or combined with continuous training, found a mean increase in VO2max of 500 milliliters per minute, compared with 400 mL per minute in the HERITAGE study described in the sidebar. The analysis also suggested that longer intervals combined with high-intensity continuous training can produce increases in VO2max in almost all relatively young adults.
It appears that intervals of 3–5 minutes are especially effective for improving VO2max. The nine studies that saw the largest increases in VO2max (~850 mL per minute) generally used intervals of 3–5 minutes with 2-minute rest periods and high-intensity continuous training.
Do We Really Need Cardio?
Given that many nonresponders identified in research studies were doing long-duration, low-intensity, continuous exercise—that is, cardio—while interval training and higher-intensity continuous exercise eliminated nonresponders in some cases, it’s worth asking: Do our clients really need cardio?
Many clients love cardio because it gives them the best results. These people thrive on taking long walks, running along the beach or in the mountains, riding an exercise bike listening to their playlist, running on a treadmill and getting lost in their thoughts, and/or swimming lap after lap. However, some clients either don’t respond to cardio or do not enjoy it (or both).
Nevertheless, many trainers prescribe cardio whether clients like it or not. Or, perhaps, the clients keep doing it because they think cardio is the way to maximize results.
Interestingly, when asked if cardio is essential to an exercise program, many trainers say their clients need it in their program. Yet based on results from the HERITAGE study, it may be safe to rethink the use of cardio for so many clients. After all, there is plenty of research and anecdotal evidence that so-called nontraditional forms of training, or “metabolic training,” can give clients better results than cardio.
To read more how science has uncovered ways to turn your nonresponders into responders in spite of their genetics, please see " Success in Our Genes and Smart Programming" in the online IDEA Library or in the April 2016 print issue of IDEA Fitness Journal. If you cannot access the full article and would like to, please contact the IDEA Inspired Service Team at (800) 999-4332, ext. 7.