Can We Improve the Functional Threshold Power Test by Adding High-Intensity Priming Arm-Crank?

The aim of the present study was to evaluate the effects of arm-crank induced priming on subsequent 20 min Functional Threshold Power Test among 11 well-trained male cyclists (18.8 ± 0.9 years; 182 ± 5 cm; 73.0 ± 6.6 kg; V˙O_2max 67.9 ± 5.1 mL·kg^-1·min^-1). Participants completed an incremental test and two maximal performance tests (MPTs) in a randomized order. Warm-up prior to MPT_low consisted of 20 min aerobic exercise and 25 s high-intensity all-out arm crank effort was added to warm-up in MPT_high. Constant intensities for the first 17 min of MPT were targeting to achieve a similar relative fatigue according to participants' physiological capacity before the last 3 min all-out spurt. Final 3 min all-out spurt power was 4.94 ± 0.27 W·kg^-1 and 4.85 ± 0.39 W·kg^-1 in MPT_low and MPT_high, respectively (not statistically different: p = 0.116; d = 0.5). Blood lactate [La] levels just before the start were higher (p < 0.001; d = 2.6) in MPT_high (5.6 ± 0.5 mmol·L^-1) compared to MPT_low (1.1 ± 0.1 mmol·L^-1). According to V˙CO₂ and net [La] data, significantly higher anaerobic energy production was detected among MPT_low condition. In conclusion, priming significantly reduced anaerobic energy contribution but did neither improve nor decrease group mean performance although effects were variable. We suggest priming to have beneficial effects based on previous studies; however, the effects are individual and additional studies are needed to distinguish such detailed effects in single athletes.