(50) WORKOUT DURATION ALTERS RELATIONSHIPS BETWEEN THE PREDICTIVE TRAITS OF PERFORMANCE DURING A HIGH-INTENSITY FUNCTIONAL TRAINING WORKOUT

Daily high-intensity functional training (HIFT) workouts are highly diverse, and each may differentially challenge a unique combination of strength, skill, and endurance across one or more movement patterns. Though it may be expected that a different set of skills and physiological traits will be relevant to completely different workouts, it remains unexplored how altering only a single programming variable might affect relevant characteristics. 

Purpose: To examine the effect of altering workout duration of an AMRAP circuit on relationships between workout performance and athlete demographics, performance capability, and training experience.

Methods: Men (n = 12) and women (n = 10) with at least 2 years of HIFT experience (29.3 ± 7.1 years, 171 ± 7 cm, 80.5 ± 15.6 kg) volunteered for a larger study about a pre-workout supplement’s effect on HIFT performance. Pre-study background information about resistance training (RT; years of training experience and maximal strength across a variety of lifts), gymnastics (years of training and competition experience, repetition maximums [RM] across several exercises), and HIFT (years of training experience, and personal best performance across several benchmark workouts) was collected before participants completed baseline body composition (via 4-compartment model), maximal vertical jump (VJ) height, 3-5 RM thruster strength, and a 2K rowing for time testing. Participants returned over the next four consecutive weeks to randomly complete a circuit of rowing (men: 9 calories; women: 7 calories), six barbell thrusters (men: 43.1 kg; women: 29.5 kg), and three box (men: 0.61 m; women: 0.51 m) jumps for ‘as many repetitions as possible’ (AMRAP) in 5 or 15 minutes after consuming the supplement or placebo. Pearson correlation coefficients were calculated between all baseline (reported and measured) measures and workout performances (total rounds, and repetitions and workload [in kg] completed over the entire workout and each exercise) during placebo conditions. Relationship differences between the 5- and 15-minute bouts were assessed using the Fisher’s r-to-z transformation procedure.

Results: Significant (p < 0.05) relationships to the nine performance measures in either the 5- or 15-minute workouts (or both) were seen across all 39 variables except for VJ height, years of training experience (RT, gymnastics [and competition experience], and HIFT), RM in strict pull-ups, 5K run time, and “MURPH” performance. More significant relationships were seen with the 5-minute workout (n = 229, average r² = 0.34) than the 15-minute workout (n = 158, average r² = 0.25), and most were to thruster workload (n = 56). Most differences between workout durations (p < 0.05) were seen with relationships to thruster repetitions (n = 17), predominantly with measured and reported strength (n = 11). Less than five relationship differences were noted for total workload, rowing calories and workload, thruster workload, and box jump workload.

Conclusion: Relevant demographic and performance (measured and reported) characteristics were differentially related to total rounds and repetitions completed, as well as with thruster and box jump repetitions, when the duration of the same HIFT circuit was extended by 10 minutes. PRACTICAL APPLICATIONS: The data suggest that the specific combination of factors relevant to HIFT workout performance may change even when altering a single programming variable such as the duration of an AMRAP.

Acknowledgements: This study was funded by Shifted, LLC.