Particularly, VPX yielded a significantly larger interaction effect between the performance tests following HIRT compared to iCHO. Repeated performance is a combined series of effort (often entailing more than one exercise modality and/or skill); hence, it is important a product has collective benefits rather than just improving one measure. Macronutrient and rate of perceived exertion Exertion levels, or even “perceived” exertion levels, during exercise may affect performance. Very

few studies have investigated the effects of PRO alone on RPE. The investigations by Backhouse et al. [36, 37] supported the supplementation of CHO to lower RPE during exercise. Kalman [38] compared the effects of CHO-only, PRO-CHO, and PRO-only BIBW2992 check details on various performance measures (i.e. resistance training), including RPE. The results did not report a ASP2215 in vitro significant difference in RPE between groups over time. This study reported similar findings with respect to differences between means and hypothesis testing via ANOVA—neither treatment was statistically significant towards reducing agility T-test, to-fatigue push-up, or 40-yard sprint RPE following HIRT. Rate of perceived exertion is a subjective measurement, and studies by Utter et al. [39–42] that examined the effects of CHO on RPE observed that RPE does not correlate with the amount of total work actually performed.

Subjects may have “felt” more fatigued after consuming a placebo compared to CHO, but there were no

mean differences in performance between groups. Similarly, the current investigation found VPX and iCHO to be equivocal in terms of the subjects’ reported RPE; in other words, this is the first study to find that VPX provides similar exertion responses to an iCHO drink. Limitations The ANOVA and t-test statistical results were not significant for any individual dependent variables. This could have been attributed to sample size and power (80%). The RM-MANOVA was not affected by the sample size and resulted in a meaningful and significant difference; this model reported a significant cumulative effect between the three performance tests. This outcome is likely attributed to the similarities between the tests (i.e., exercise Lck performance variables) and their collective impact; as the variables were added into the model their compounded effects on each other became statistically apparent. Physical activity is a cumulative action often involving a combination of endurance, speed, agility, power and balance to name a few. It may be valuable to see cumulative effects than singular effects in exercise performance for athletes and exercisers who rely on more than one energy system and skill to complete a task or activity. Beyond the statistical limitations, state anxiety appeared to be a limitation for all subjects. It is possible the subjects had apprehension leading into the second workout test.