Richard Page

Biomechanical and physiological response to a contemporary soccer match-play simulation.

Abstract Page, RM, Marrin, K, Brogden, CM, and Greig, M. Biomechanical and physiological response to a contemporary soccer match-play simulation. J Strength Cond Res 29(10): 2860–2866, 2015—The intermittent activity profile of soccer match play increases the complexity of the physical demands. Laboratory models of soccer match play have value in controlled intervention studies, developed around manipulations of the activity profile to elicit a desired physiological or biomechanical response. Contemporary notational analyses suggest a profile comprising clusters of repeat sprint efforts, with implications for both biomechanical and physiological load. Eighteen male soccer players completed a 90-minute treadmill protocol based on clusters of repeat sprint efforts. Each 15-minute bout of exercise was quantified for uniaxial (medial-lateral [PLML], anterior-posterior [PLAP], and vertical [PLV]) and triaxial PlayerLoad (PLTotal). The relative contributions of the uniaxial PlayerLoad vectors (PLML%, PLAP%, and PLV%) were also examined. In addition to rating of perceived exertion, the physiological response comprised heart rate, blood lactate concentration, and both peak and average oxygen consumption. Triaxial PlayerLoad increased (p = 0.02) with exercise duration (T 0–15 = 206.26 ± 14.37 a.u. and T 45–60 = 214.51 ± 14.97 a.u.) and remained elevated throughout the second half. This fatigue effect was evident in both the PLML and PLAP movement planes. The mean relative contributions of PLV%:PLAP%:PLML% were consistent at ∼48:28:23. The physiological response was comparable with match play, and a similar magnitude of increase at ∼5% was observed in physiological parameters. Changes in PlayerLoad might reflect a change in movement quality with fatigue, with implications for both performance and injury risk, reflecting observations of match play. The high frequency of speed change elicits a 23% contribution from mediolateral load, negating the criticism of treadmill protocols as “linear.”

Contemporary approaches to isokinetic strength assessments in professional football players

ABSTRACT Purpose: To assess traditional and novel isokinetic strength characteristics of the eccentric knee flexor (eccKF) and concentric knee extensor (conKE) musculature, 26 professional football players completed bilateral conKE and eccKF contractions at angular velocities of 180, 270, and 60° · s−1. Method: Peak torque (PT), angle of peak torque (APT), angle-specific torque (AST) analysed every 10° between 40° and 70°, functional range (FR), and dynamic control ratios (DCR) calculated from both the PT (DCRPT) and AST data (DCRAST) were analysed. Results: The PT, APT, and FR data elicited significant contraction*angular velocity interactions (P < 0.001). Significant main effects for contraction*angular velocity*angle and contraction*angular velocity*limb*angle interactions (P ≤ 0.001) were identified for AST data. The DCRPT data elicited a significant main effect for angular velocity (P < 0.001) and limb (P = 0.018), whereas the DCRAST data were significantly different across angles (P < 0.001) and elicited a significant (P = 0.002) limb*angle interaction. Conclusion: Traditional analysis variables utilised for isokinetic strength assessments in football may not be appropriate and/or sensitive enough to identify injury risk. Practitioners should utilise the novel metrics proposed in the current study and conduct assessments across a range of joint angles and angular velocities.

Quantifying the Physical Response to a Contemporary Amateur Boxing Simulation

Abstract Finlay, MJ, Greig, M, and Page, RM. Quantifying the physical response to a contemporary amateur boxing simulation. J Strength Cond Res 32(4): 1005–1012, 2018—This study examined the physical response to a contemporary boxing-specific exercise protocol (BSEP), based on notational analysis of amateur boxing. Nine male senior elite amateur boxers completed a 3 × 3-minute BSEP, with a 1-minute passive recovery period interspersing each round. Average (HRave) and peak (HRpeak) heart rates, average (V[Combining Dot Above]O2ave) and peak oxygen consumptions (V[Combining Dot Above]O2peak), blood lactate (BLa) concentrations, rating of perceived exertion, and both triaxial and uniaxial PlayerLoad metrics were recorded during the completion of the BSEP. Blood lactate concentration increased significantly in each round (Round 1 = 2.4 ± 1.3 mmol·L−1; Round 2 = 3.3 ± 1.7 mmol·L−1; Round 3 = 4.3 ± 2.6 mmol·L−1). Significantly lower HRave and HRpeak values were found in the first round (HRave: 150 ± 15 b·min−1; HRpeak: 162 ± 12 b·min−1) when compared with the second (HRave: 156 ± 16 b·min−1; HRpeak: 166 ± 13 b·min−1) and third (HRave: 150 ± 15 b·min−1; HRpeak: 169 ± 14 b·min−1). No significant differences were found in any of the V[Combining Dot Above]O2 or PlayerLoad metrics recorded during the BSEP. The BSEP based on notational analysis elicited a fatigue response across rounds, confirming its validity. The BSEP can be used as a training tool for boxing-specific conditioning with implications for reduced injury risk, and to assess the physical response to boxing-specific interventions. Moreover, the BSEP can also be manipulated to suit all levels of participants or training phases, with practical applications in performance monitoring and microcycle periodization.

Acute adaptations and subsequent preservation of strength and speed measures following a Nordic hamstring curl intervention: a randomised controlled trial

ABSTRACT This randomised controlled trial investigated changes in eccentric hamstring strength, 10m sprint speed, and change-of-direction (COD) performance immediately post Nordic hamstring curl (NHC) intervention and following a 3-week detraining period. Fourteen male team sports athletes were randomised to a do-as-usual control group (CG; n = 7) or to a NHC intervention group (NHC; n = 7). Isokinetic dynamometry at 180°/s evaluated eccentric hamstring strength immediately post-intervention as the primary outcome measure. Secondary outcomes included 10 m sprint time and COD. Each outcome was measured, pre, immediately post-intervention and following a 3-week detraining period. Immediately post-intervention significant group differences were observed in the NHC group for eccentric hamstring strength (31.81 Nm−1 vs. 6.44 Nm−1, P = 0.001), COD (−0.12 s vs. 0.20 s; P = 0.003) and sprint (- 0.06 s vs. 0.05 s; P = 0.024) performance. Performance improvements were maintained following a detraining period for COD (−0.11 s vs. 0.20 s; P = 0.014) and sprint (−0.05 s vs. 0.03 s, P = 0.031) but not eccentric hamstring strength (15.67 Nm−1 vs. 6.44 Nm−1, P = 0.145) These findings have important implications for training programmes designed to reduce hamstring injury incidence, whilst enhancing physical qualities critical to sport.

The physical response to a simulated period of soccer-specific fixture congestion

Abstract Page, RM, Marrin, K, Brogden, CM, and Greig, M. Physical response to a simulated period of soccer-specific fixture congestion. J Strength Cond Res 33(4): 1075–1085, 2019—The aim of this study was to assess the physiological, perceptual, and mechanical measures associated with the completion of a simulated period of short-term soccer-specific fixture congestion. Ten male semiprofessional soccer players completed 3 trials of a treadmill-based match simulation, with 48 hours interspersing each trial. A repeated measures general linear model identified significantly (p = 0.02) lower knee flexor peak torque (PT) recorded at 300°·s−1 in the second (141.27 ± 28.51 N·m) and third trials (139.12 ± 26.23 N·m) when compared with the first trial (154.17 ± 35.25 N·m). Similarly, muscle soreness (MS) and PT data recorded at 60°·s−1 were significantly (p ⩽ 0.05) different in the third trial (MS = 42 ± 25 a.u; PT60 = 131.10 ± 35.38 N·m) when compared with the first trial (MS = 29 ± 29 a.u; PT60 = 145.61 ± 42.86 N·m). Significant (p = 0.003) differences were also observed for mean electromyography (EMGmean) of bicep femoris between the third trial (T0–15 = 126.36 ± 15.57 &mgr;V; T75–90 = 52.18 ± 17.19 &mgr;V) and corresponding time points in the first trial (T0–15 = 98.20 ± 23.49 &mgr;V; T75–90 = 99.97 ± 39.81 &mgr;V). Cumulative increases in perceived exertion, heart rate, oxygen consumption, blood lactate concentrations, EMGmean, and PlayerLoad (PL) were recorded across each trial. Muscle soreness and PT were also significantly different after trial. There were, however, no significant main effects or interactions for the salivary immunoglobulin A and the medial-lateral PL metrics. These data suggest a biomechanical and muscular emphasis with residual fatigue, with implications for injury risk and the development of recovery strategies.