A clinical trial was done to see the changes in physical performance with High Intensity Interval Training (HIIT) and a pre-workout supplement compared to a placebo group. The interval training was done for a period of three weeks (1). This study was the first trial done with HIIT and pre-workout supplementation and needs further research. The researchers found that if a pre-workout supplement is taken 30 minutes before interval training, there can be improvements in aerobic exercise and lean body mass (LBM).
In this study there were 24 physically active men and women around 20 years old. This was a randomized, single-blinded, placebo controlled trial. Each participant came to the laboratory 18 times. The first 3 visits were familiarization sessions. In these sessions they did running tests to determine the participants maximal oxygen uptake (VO2max). The visits 4-6 and 16 – 18 were pre-training and post-training test sessions. These included the same running tests as the first 3 visits, but the participants had been assigned to a placebo (PL, 11 participants) or a pre-workout supplement (Game Time, GT, 13 participants). Visits 7-15 were three weeks of HIIT (5 sets of 2 minutes work 1 minute rest). At the end of the study they found that (77%) of the GT group increased aerobic running performance, compared to (64%) of the PL group. VO2max increased in GT (77%) and PL (73%). LBM increased in GT (69%) and PL (55%)
For this study it was a small sample size, done for a short period of time. They had participants in their sample size that was appropriate for the intended audience. The author concluded that small supplementation of a pre-workout before HIIT for 3 weeks will significantly improve aerobic training and may be supportive in increasing LBM. To strengthen these results a study with more participants and comparing both genders separately for an extended period of time needs to be done.
This is the first study to compare HIIT with pre-workout supplements. Other studies have inspected the outcome of similar pre-workout supplements on different types of training. One study that had 24 males take a pre- and post-workout supplement for six-weeks doing resistance training found increases in LBM by almost (5%) compared to placebo groups (2). Another study with 20 resistance-trained men took only a pre-workout supplement and found an increase in LBM by (7.8%), and the placebo group increased by (3.6%) (3). The composition of the pre-workout supplement in all 3 studies was very similar in composition, and they both lead to an increase in LBM. In one other study, both men and women consuming a pre-workout supplement before resistance training were studied. In the end of their study they said that there was no statistical significance in the change of body composition, but increased energy levels (4).
As pre-workout supplements become more popular with those that are physically active there are more studies being done on whether they will help improve performance. This study is the first to focus on HIIT, and not on resistance training. While the results show a positive result from using the supplement, caution needs to be taken before using a pre-workout supplement. More studies need to be done to see if there are actual benefits to using a pre-workout supplement on aerobic and anaerobic performance.
Original Article: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2854104/
References
- Smith AE, Fukuda DH, Kendall KL, Stout JR. The effects of a pre-workout supplement containing caffeine, creatine, and amino acids during three weeks of high-intensity exercise on aerobic and anaerobic performance. J Int Soc Sports Nutr. 2010;7(1):10.
- Ormsbee MJ, Mandler WK, Thomas DD, et al. The effects of six weeks of supplementation with multi-ingredient performance supplements and resistance training on anabolic hormones, body composition, strength, and power in resistance-trained men. J Int Soc Sports Nutr. 2012;9(1):49.
- Lowery RP, Joy JM, Dudeck JE, et al. Effects of 8 weeks of Xpand® 2X pre workout supplementation on skeletal muscle hypertrophy, lean body mass, and strength in resistance trained males. J Int Soc Sports Nutr. 2013;10(1):44.
- Kedia AW, Hofheins JE, Habowski SM, Ferrando AA, Gothard MD, Lopez HL. Effects of a Pre-workout Supplement on Lean Mass, Muscular Performance, Subjective Workout Experience and Biomarkers of Safety. Int J Med Sci. 2014;11(2):116-26.
Reviewed by Viktoriya Wolff