Various forms of rope training have been in existence since the 1800s. Randy Hetrick developed TRX equipment and the associated Suspension Training bodyweight exercises in the 1990s. TRX is a form of resistance training that includes bodyweight exercises, in which a variety of multi-planar, compound exercise movements can be performed. These exercises aim to develop strength, balance, flexibility, and joint stability simultaneously. TRX Suspension Training develops physical strength while using functional movements and dynamic positions. A typical TRX Suspension Training classes consists of traditional and functional resistance-training exercises performed on the TRX Suspension Training system. For example, a class might include some combination of the following exercises: lunges, push-ups, pull-ups, chest presses, rows, squats, side arm planks with rotation, and curls. For each session, individuals rotate to different stations every 60 or 90 seconds, depending on the class design. Additionally, after individuals rotate off TRX stations, they can incorporate various cardiorespiratory exercise stations, such as agility ladder drills or kettlebell swings, into their overall routines.
Exercise intensity is arguably the most critical component of the exercise prescription model. Failure to meet minimal threshold values may result in lack of a training effect, whereas a program of too high intensity could lead to overtraining and negatively impact adherence to an exercise program. Research indicates participation in TRX Suspension Training exercise can be classified as moderate, according to various organizations' definition of physical activity intensity. For example, moderate exercise intensity in relative terms has been defined as 40%–59% of HRR/VO2R. According to research, a typical TRX Suspension Training class elicits HRR (59.9%) and VO2R (45.9%) values that fall within the moderate relativeintensity category.
In the 2008 United States physical-activity guidelines report, moderate-intensity physical activity in absolute metabolic terms has been classified as 3–6 metabolic equivalents (METs). Research has found that the MET response to TRX Suspension Training exercise averages 5.8 METs. This is an important finding, given the fact that moderate-intensity exercise has been widely recommended for health benefits. The MET values of TRX Suspension Training compare favorably to more traditional land-based aerobicexercise values and nontraditional exercise values. For instance, treadmill and over-ground brisk walking at 4.0 miles per hour (6.4 kph) is an equivalent moderate-intensity physical activity at 4.9 METs. Likewise, a 176-lb. (80-kg) individual cycling between 50 and 100 watts will elicit a MET value ranging from 4.0 to 6.0 METs.
For the improvement and maintenance of cardiorespiratory fitness, the ACSM has recommended a target energy expenditure of 150–400 kilocalories per day. Research has found that participation in a 60 minute TRX Suspension Training class yields a mean energy expenditure of ~400 kilocalories that satisfies the ACSM recommendations for daily energy expenditure. This volume of energy expenditure is comparable to other nontraditional alternative activities. For instance, it has been reported that participation in a one-hour session of Nintendo Wii Sports elicited a mean energy expenditure of ~250 kilocalories per session. It has also been demonstrated that participation in a 40-minute Ultimate Frisbee match elicited a total energy expenditure of ~475 kilocalories per match.
Research findings demonstrate that TRX Suspension Training confers similar health benefits when compared to those achieved from traditional aerobic training. For example, one study reported that participation in a 60-minute TRX Suspension Training class, three days per week for eight weeks, resulted in significant improvements in resting systolic ad diastolic blood pressure, percentage of body fat, and waist circumference. Additionally, this same study showed that muscular strength and endurance were also improved with chronic TRX Suspension Training. It has been reported that increased muscular fitness is associated with a reduced risk of all-cause mortality, so these findings have long-term health implications. Another study compared TRX Suspension Training versus traditional resistance training on various measures of strength, core endurance, flexibility, balance, and body composition. The research findings from this study indicated that TRX Suspension Training improved, in both younger and middle-aged adults, various muscular fitness variables, such as lower body strength and core strength, that are generally associated with traditional resistance training. The researchers concluded that their findings could prove useful to individuals looking for more training options to gain both core endurance and muscular strength simultaneously as well as enhancing the diversity of their exercise choices.
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Ainsworth, Barbara E., et al. “Compendium of Physical Activities: A Second Update of Codes and MET Values.” Medicine and Science in Sports and Exercise 43, no. 8 (August 2011): 1575–81.
Janot, Jeffrey, et al. “Effects of TRX Versus Traditional Resistance Training Programs on Measures of Muscular Performance in Adults.” Journal of Fitness Research 2, no. 2 (December 2013): 23–38.
Smith, Leslie E., et al. “The Acute and Chronic Health Benefits of TRX Suspension Training® in Healthy Adults.” International Journal of Research in Exercise Physiology 11, no. 2 (May 2016): 1–15.
Smith, Leslie E., et al. Investigating the Acute and Chronic Health Benefits of TRX® Suspension Training®. American Council on Exercise. https://www.acefitness.org/certifiedarticle/6102/ace-sup-sup-sponsoredresearch-investigating (accessed February 10, 2017).
“What Is TRX Training?” Fitness Anywhere LLC. https://www.trxtraining.com/suspension-training.htm (accessed February 10, 2017).
American College of Sports Medicine (ACSM), 401 W. Michigan St., Indianapolis, IN, 46202-3233, (317) 637-9200, Fax: (317) 634-7817, http://www.acsm.org .
American Council on Exercise, 4851 Paramount Dr., San Diego, CA, 92123, (858) 576-6500, (888) 825-3636, ext. 782, Fax: (858) 576-6564, https://www.acefitness.org .
Lance C. Dalleck, PhD