RSS training is a novel training method with potential for the improvement of sprint performance, but its performance benefits over URS training remain to be conclusively demonstrated. Between-study comparisons are limited primarily by discrepancies in the training status and phase of the participants, and sled load prescription. Future work is required to define the optimal load and volume for RSS depending on the specific components of sprint performance to be enhanced.

This study may encourage further research to confirm the usefulness of very-heavy sled in this context.

McGuinness, A, Malone, S, Petrakos, G, and Collins, K. The physical and physiological demands of elite international female field hockey players during competitive match play. J Strength Cond Res 33(11): 3105–3113, 2019—The aim of the current investigation was to quantify the physical and physiological demands of elite international female field hockey match play across halves of play. Thirty-eight participants (24 ± 5 years; 173 ± 5 cm; 72 ± 5 kg) took part in 19 competitive matches during the 2014–2015 season. Participants were monitored with global positioning system technology and heart rate monitors. Players were categorized based on 3 different playing positions. Activity was categorized into total (m), high-speed running distance (m; >16 km·h−1), and relative distance (RD) (m·min−1) due to the use of rolling substitutions. Heart rate was classified based on the percentage of players' individual peak heart rate (HRpeak) determined by a Yo-Yo intermittent recovery level 1 test. Players spent on average 44 ± 7 minutes in match play. The total distance (TD) covered was 5,558 ± 527 m (125 ± 23 m·min−1) with 589 ± 160 m (13 ± 4 m·min−1) completed at high speed. Defenders covered a greater TD compared with other positions of play (p ≤ 0.001). Midfield players covered a greater distance at high speed (p ≤ 0.001) with the forwards having a higher relative distance (p ≤ 0.001). The HRpeak of the players was 199 ± 1 b·min−1 with a mean exercise intensity of 86 ± 7.8% of HRpeak. The time spent >85% HRpeak decreased significantly across the halves (p = 0.04, η2 = 0.09, small). Defenders were found to spend more time >85% HRpeak when compared with forwards (p ≤ 0.001). The current investigation provides normative data that coaches should consider when constructing training regimen.

Resisted sled sprint (RSS) training is an effective modality for the improvement of linear sprint speed. Previous methods of RSS load prescription e.g. an absolute load or as a percentage of body mass (%BM), do not account for inter-individual differences in strength, power or speed characteristics, although the 'maximum resisted sled load' (MRSL) method of RSS load prescription may provide a solution. MRSL is defined as the final RSS load before an athlete can no longer accelerate between two phases (10-15 m and 15-20 m) of a 20 m linear sprint. However, the MRSL test has not been analysed for reliability. Additionally, MRSL performance has not been compared to the outcome of other performance tests. The primary aim of this study was to investigate the reliability of the MRSL testing protocol in female field sport athletes. Participants (age, 20.8 ± 1.9 y; body mass, 64.3 ± 8.4 kg; height, 1.66 ± 0.65 m) tested for anthropometric measurements, strength and power performance testing and twice for MRSL. MRSL values ranged from 20.7 to 58.9%BM. MRSL test-retest reliability intraclass correlation coefficient, confidence intervals and coefficient of variations were 0.95, 0.85-0.98 and 7.6%, respectively. MRSL was 'moderately' and 'strongly' correlated with a number of anthropometric and performance tests (p < 0.05) including % fat free mass, countermovement jump, loaded countermovement jump, rate of force development, horizontal jump and horizontal bound performance. MRSL is a reliable measure for determining the RSS load at which an individual can no longer accelerate during a single RSS effort over 0-20 m. MRSL also accounts for inter-individual variation in body composition, power and speed characteristics of female field sport players.

Monahan, M, Petrakos, G, and Egan, B. Physiological and perceptual responses to a single session of resisted sled sprint training at light or heavy sled loads. J Strength Cond Res 36(10): 2733-2740, 2022-The acute physiological and perceptual responses to a single session of resisted sled sprint (RSS) training are largely unexplored, nor have differences, if any, between male and female athletes been compared. Team field sport athletes (n 5 27; male/female, 15/12; 21.1 6 2.7 years) were assessed for Maximal Resisted Sled Load (MRSL) from which light (L-RSS, 30%MRSL) and heavy (H-RSS, 80%MRSL) sled loads were prescribed. On separate occasions in random order, 2 training sessions of 12 3 20 m RSS repetitions at either L-or H-RSS were performed, and assessments of physiological and perceptual responses were performed before (PRE), during, after (POST) and 24 hours after (+24 hours POST) each session. Compared to unresisted sprints, velocity decrements of 7.5 6 2.2 and 22.7 6 8.1% were produced by L-RSS and H-RSS, respectively. Heart rate, blood lactate, and ratings of perceived exertion were higher in H-RSS compared to L-RSS. Decrements in 20 m sprint and countermovement jump performance observed at POST had returned to PRE values at +24 hours POST. Except for a higher heart rate (;7-12 b•min 21 ) in females during the respective sessions, responses to L-and H-RSS were generally similar between males and females. A single session of heavy RSS training is more demanding than light RSS training when matched for sprint number and distance, but measures of lower limb power and sprint performance return to pre-training levels within 24 hours regardless of sled load. Males and females respond similarly to a single session of RSS training when individualized, relative intensity sled loads are prescribed.