High-performing masters athletes use more-controlled pacing strategies than their lower-ranked counterparts during a competitive marathon, independent of age and gender.

THIS ARTICLE EXAMINES THE APPLICATION OF A VARIETY OF MODALITIES TO ELICIT A POSTACTIVATION POTENTIATION (PAP) RESPONSE IN SPRINTING. WE PRESENT THE EXISTING LITERATURE ON THE ACUTE EFFECTS OF BACK SQUATS, POWER CLEANS, PLYOMETRICS, AND SLED PULLING ON SPRINT DISTANCES RANGING FROM 5 TO 50 M. WE ALSO DISCUSS AND PROVIDE AN EXAMPLE OF HOW COACHES CAN ASSESS THE INDIVIDUAL EFFECTS OF PAP PROTOCOLS ON THEIR ATHLETES TO IDENTIFY WHETHER A PROTOCOL ELICITS AN ACUTE IMPROVEMENT OR IMPAIRMENT IN PERFORMANCE. FINALLY, WE PROVIDE PRACTICAL RECOMMENDATIONS ON HOW COACHES CAN INCORPORATE THESE METHODS INTO A SPRINT TRAINING SESSION.

The aim of this study was to assess the concurrent validity of the Optojump™ system (Microgate, Bolzano, Italy) versus a force platform in the estimation of temporal and reactive strength measures. In two separate investigations, twenty physically active males performed double-leg and single-leg drop jumps from a box height of 0.3 m and a 10 s vertical bilateral hopping test. Contact time, flight time and total time (the sum of contact and flight time) were concurrently assessed during single and double-leg drop jumps and during hopping. Jump height, the reactive strength index and the reactive strength ratio were also calculated from contact time and flight time. Despite intraclass correlation coefficients (ICCs) for all variables being close to 1 (ICC > 0.975), a significant overestimation was found in contact time (0.005 ± 0.002 s) and underestimations in flight time (0.005 ± 0.003 s), the reactive strength index (0.04 ± 0.02 m·s-1) and the reactive strength ratio (0.07 ± 0.04). Overestimations in contact time and underestimations in flight time were attributed to the physical design of the Optojump™ system as the transmitter and receiver units were positioned 0.003 m above the floor level. The Optojump™ demonstrated excellent overall temporal validity with no differences found between systems for total time. Coaches are advised to be consistent with the instrumentation used to assess athletes, however, in the case of comparison between reactive strength values collected with the Optojump™ and values collected with a force platform, regression equations are provided.

The method of assessing reactive strength (RSI vs RSR) may be influenced by the performance strategies adopted, that is, whether athletes achieve their best reactive strength scores via low CTs, high JHs, or a combination. Coaches are advised to limit the variability in performance strategies by implementing upper and/or lower CT thresholds to accurately compare performances between individuals.

This study describes the results of a survey of resistance training practices of sprint coaches. This study investigated why sprint coaches prescribe resistance training to their athletes, what exercises they select, and what factors are involved with their selection.Forty-one of 73 (56%) sprint coaches with mean 6 SD coaching experience of 8.4 6 6.4 years were included in this study. Coaches completed an online questionnaire consisting of 5 sections: (a) informed consent, (b) coach background information, (c) coach education and qualifications, (d) coaches' views on resistance training, and (e) exercise selection and preference. The results showed that coaches prescribe resistance training to their sprint athletes to develop strength and power, which they believe will transfer to sprint performance. Coaches prescribed a wide variety of traditional, ballistic, and plyometric exercises, with the hurdle jump found to be the most widely prescribed exercise (93% of coaches surveyed). Coaches selected exercises for a variety of reasons; however, the 3 most prominent reasons were: (a) performance adaptations; (b) practicality; and (c) the targeting of muscles/muscle groups. Coaches prioritized exercises that specifically developed strength, power, and reactive strength for their sprint athletes. This research can be used to develop educational resources for sprint coaches who wish to use resistance training with their athletes. In addition, sprint coaches can use the data presented to expand their current exercise repertoire and resistance training practices.

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Healy, R, Smyth, C, Kenny, IC, and Harrison, AJ. Influence of reactive and maximum strength indicators on sprint performance. J Strength Cond Res XX(X): 000-000, 2018-The primary aim of this study was to assess the relationship between reactive and maximal strength measures with 40 m sprint performance and mechanical properties. Fourteen male and 14 female sprinters participated in this study. On the first day, subjects performed 40 m sprints with 10-m split times recorded in addition to maximal theoretical velocity, maximal theoretical force and peak horizontal power, which were calculated from force-velocity relationships. On the second day, subjects performed isometric midthigh pulls (IMTPs) with peak force (PF) and relative PF calculated, drop jumps (DJs) and vertical hopping where the reactive strength index (RSI) was calculated as jump height (JH) divided by contact time (CT). Pearson correlations were used to assess the relationships between measures and independent samples t-tests were used to assess the differences between men and women. No significant correlations were found between DJ and hopping RSI and sprint measures. A significant strong positive correlation was found between IMTP PF and peak horizontal power in men only (r = 0.61). The male sprinters performed significantly better in all recorded measures apart from hopping (CT, JH and RSI) and DJ CT where no significant differences were found. The lack of association between reactive and maximal strength measures with sprint performance is potentially because of the test's prolonged CTs relative to sprinting and the inability to assess the technical application of force. Several methods of assessing reactive strength are needed that can better represent the demands of the distinct phases of sprinting e.g., acceleration, maximum velocity.

Warm-up protocols are commonly used to acutely enhance the performance of dynamic activities. This study examined the acute effect of low-load gluteal exercises on the biomechanics of single-leg drop jumps. Eight men and seven women (18-22 years old) performed 10 single-leg drop jumps on three separate days. The gluteal exercises were performed within the warm-up on day 2. Contact time, flight time, peak vertical ground reaction force (GRF), rate of force development, vertical leg-spring stiffness, and reactive strength index were determined. A repeated measures analysis of variance was used to examine differences on all variables across days. Significant differences were found for contact time, peak GRF, and flight time between days 1 and 2 and for flight time between days 1 and 3 (p < or = 0.05) with no significant difference in any variables between days 2 and 3. This suggested that the improvements in day 2 were due to practice effects rather than the gluteal activation exercises. In addition, a typical error analysis was used to determine individual responses to the gluteal exercises. The results using this analysis showed no discernible response pattern of enhancement or fatigue for any participant.