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Amber E. Rowell, Robert J. Aughey, Will G. Hopkins, Andrew M. Stewart and Stuart J. Cormack

Objective measures of recovery from football match play could be useful for assessing athletes’ readiness to train, if sensitive to preceding match load.

Purpose:

To identify the sensitivity of countermovement-jump (CMJ) performance and concentration of salivary testosterone and cortisol relative to elite football match load.

Methods:

CMJ performance and salivary hormones were measured in 18 elite football players before (27, 1 h) and after (0.5, 18, 42, 66, 90 h) 3 consecutive matches. Match load was determined via accelerometer-derived PlayerLoad and divided into tertiles. Sensitivity of CMJ performance and hormone concentrations to match load was quantified with t statistics and magnitude-based inferences (change in mean as % ± 90% confidence interval) derived with a linear mixed model.

Results:

Jump height was reduced in medium and high load at 0.5 h (10% ± 7% and 16% ± 8%) and 18 h (7% ± 4% and 9% ± 5%) postmatch. There was a 12% ± 7% reduction in ratio of flight time to contraction time (FT:CT) in high load at 0.5 h post, with reductions in medium and high load at 18 h. Reductions in FT:CT persisted at later postmatch time points than changes in jump height. Increased cortisol (range 55–165%) and testosterone (range 17–20%) were observed in all match loads at 0.5 h post, with individual variability thereafter.

Conclusions:

Measures of CMJ performance and hormonal concentrations were sensitive to levels of A League football match load. Although jump height was reduced immediately postmatch, FT:CT provided a more sensitive measure of recovery. Football match play induces an acute hormonal response with substantial individual variability thereafter.

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Thimo Wiewelhove, Christian Raeder, Tim Meyer, Michael Kellmann, Mark Pfeiffer and Alexander Ferrauti

Purpose:

To investigate the effect of repeated use of active recovery during a 4-d shock microcycle with 7 high-intensity interval-training (HIT) sessions on markers of fatigue.

Methods:

Eight elite male junior tennis players (age 15.1 ± 1.4 y) with an international ranking between 59 and 907 (International Tennis Federation) participated in this study. After each training session, they completed 15 min of either moderate jogging (active recovery [ACT]) or passive recovery (PAS) with a crossover design, which was interrupted by a 4-mo washout period. Countermovement-jump (CMJ) height, serum concentration of creatine kinase (CK), delayed-onset muscle soreness (DOMS), and perceived recovery and stress (Short Recovery and Stress Scale) were measured 24 h before and 24 h after the training program.

Results:

The HIT shock microcycle induced a large decrease in CMJ performance (ACT: effect size [ES] = –1.39, P < .05; PAS: ES = –1.42, P < .05) and perceived recovery (ACT: ES = –1.79, P < .05; PAS: ES = –2.39, P < .05), as well as a moderate to large increase in CK levels (ACT: ES = 0.76, P > .05; PAS: ES = 0.81, P >.05), DOMS (ACT: ES = 2.02, P < .05; PAS: ES = 2.17, P < .05), and perceived stress (ACT: ES = 1.98, P < .05; PAS: ES = 3.06, P < .05), compared with the values before the intervention. However, no significant recovery intervention × time interactions or meaningful differences in changes were noted in any of the markers between ACT and PAS.

Conclusions:

Repeated use of individualized ACT, consisting of 15 min of moderate jogging, after finishing each training session during an HIT shock microcycle did not affect exercise-induced fatigue.

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Lawrence W. Judge and Jeanmarie R. Burke

Purpose:

To determine the effects of training sessions, involving high-resistance, low-repetition bench press exercise, on strength recovery patterns, as a function of gender and training background.

Methods:

The subjects were 12 athletes (6 males and 6 females) and age-matched college students of both genders (4 males and 4 females). The subjects completed a 3-wk resistance training program involving a bench press exercise, 3 d/wk, to become familiar with the testing procedure. After the completion of the resistance training program, the subjects, on three consecutive weeks, participated in two testing sessions per week, baseline session and recovery session. During the testing sessions, subjects performed fve sets of the bench press exercise at 50% to 100% of perceived fve repetition maximum (5-RM). Following the weekly baseline sessions, subjects rested during a 4-, 24-, or 48-h recovery period. Strength measurements were estimates of one repetition maximum (1-RM), using equivalent percentages for the number of repetitions completed by the subject at the perceived 5-RM effort of the bench press exercise.

Results:

The full-factorial ANOVA model revealed a Gender by Recovery Period by Testing Session interaction effect, F(2, 32) = 10.65; P < .05. Among male subjects, decreases in estimated 1-RM were detected at the 4- and 24-h recovery times. There were no differences in muscle strength among the female subjects, regardless of recovery time.

Conclusions:

For bench press exercises, using different recovery times of 48 h for males and 4 h for females may optimize strength development as a function of gender.

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Carrie Plaskett, Peter M. Tiidus and Lori Livingston

Ten volunteers (19-23 years old) performed 9 sets of 12 bilateral knee-extension exercises at 60% 1RM. Following exercise, 4 ultrasound treatments (5-cm transducer head, 1.0-MHz frequency, pulsed mode at 1.0 W/cm2) were applied for 8 min daily to the quadriceps muscle of a randomly selected treatment leg. The placebo leg received similar treatment with the ultrasound apparatus turned off. Knee-extension peak torque values and delayed onset muscle soreness (DOMS) were assessed on each leg prior to exercise and at 20 min and 24, 48, 72, and 96 hr postexercise. Postexercise peak torques declined to 60-70% of preexercise values and returned to normal by 96 hr. DOMS sensation peaked 24 hr postexercise and diminished thereafter. No significant differences in peak torque or DOMS were noted between ultrasound- or placebo-treated legs at any time postexercise. Hence ultrasound, as applied in this study, does not appear to be effective in enhancing postexercise muscle strength recovery or in diminishing DOMS.

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Jose Morales, Emerson Franchini, Xavier Garcia-Massó, Mónica Solana-Tramunt, Bernat Buscà and Luis-Millán González

Purpose:

To adapt the work endurance recovery (WER) method based on randori maximal time to exhaustion (RMTE) for combat situations in judo.

Methods:

Eleven international-standard judo athletes (7 men and 4 women; mean age 20.73 ± 2.49 y, height 1.72 ± 0.11 m, body mass 67.36 ± 10.67 kg) were recruited to take part in the study. All participants performed a maximal incremental test (MIT), a Wingate test (WIN), a Special Judo Fitness Test (SJFT), and 2 RMTE tests. They then took part in a session at an international training camp in Barcelona, Spain, in which 4 methods of load quantification were implemented: the WER method, the Stagno method, the Lucia method, and the session rating of perceived exertion (RPEsession).

Results:

RMTE demonstrated a very high test–retest reliability (intraclass correlation coefficient = .91), and correlations of the performance tests ranged from moderate to high: RMTE and MIT (r = .66), RMTE and WIN variables (r = .38–.53), RMTE and SJFT variables (r = .74–.77). The correlation between the WER method, which considers time to exhaustion, and the other systems for quantifying training load was high: WER and RPEsession (r = .87), WER and Stagno (r = .77), WER and Lucia (r = .73). A comparative repeated-measures analysis of variance of the normalized values of the quantification did not yield statistically significant differences.

Conclusions:

The WER method using RMTE is highly adaptable to quantify randori judo sessions and enables one to plan a priori individualized training loads.

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Avery D. Faigenbaum, James E. McFarland, Neil A. Kelly, Nicholas A. Ratamess, Jie Kang and Jay R. Hoffman

The purpose of this study was to examine the influence of recovery time following a dynamic warm-up (DY) and a static stretch warm-up (SS) on power performance in adolescent athletes. Following baseline measures, 19 males (16.5 ± 1.1 yrs) performed the vertical jump (VJ) and seated medicine ball toss (MB) at the following time points after DY and SS: 2, 6, 10, 14, 18, 22 min. Analysis of variance revealed that VJ was significantly greater following DY than SS at 2, 6, 10, 14 and 18 min. Main effects indicated a significant increase in VJ from baseline at 2 and 6 min following DY (2.6–3.9%) and a significant decrease in VJ from baseline at 2, 6, 10, 14 and 18 min following SS (–3.2% to –7.0%). No significant interaction effects between DY and SS were observed for MB. These findings indicate that lower body power performance in male adolescent athletes can be enhanced following DY as compared with SS during the first 18 min of the post warm-up period.

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Jennifer K. Coffeng, Esther M. van Sluijs, Ingrid J.M. Hendriksen, Willem van Mechelen and Cécile R.L. Boot

Background:

Research is needed to better understand the associations between during-work and after-work-hours physical activity and relaxation and need for recovery (NFR), so a study of these variables in office workers at a financial service provider was undertaken.

Methods:

Self-reported baseline data of 412 employees (mean age = 41.3 y; 39.6% women) were used. Linear regression analyses were performed to test associations of physical activity, relaxation, detachment, and breaks at work with NFR.

Results:

A lower NFR was significantly positively associated with standing, stair climbing, active lunch break, relaxation at work, detachment at work, physical detachment at work, relaxation at home, and detachment at home. In the multiple model, a lower NFR was independently positively associated with frequency of stair climbing, minutes spent in leisure activities, detachment at work, physical detachment at work, and relaxation and detachment at home (P < .05). Significant effect modification indicated that the positive association between relaxation at home and NFR was stronger with high job demands.

Conclusion:

Although prospective evidence is necessary to confirm the causal relationships, our findings suggest that engaging in stair climbing, leisure activities, (physical) detachment at work, relaxation and detachment after work is associated with a lower NFR. For future work site health promotion initiatives, interventions might be targeted at improving physical activity and relaxation.

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Vassilis Vardaxis and T. Blaine Hoshizaki

This paper describes and interprets joint and segmental power patterns as functional characteristics of the leg movement in terms of generation, absorption, and transfer of power during the recovery phase of the sprinting stride. In addition, a comparison of the power patterns between advanced and intermediate sprinters was undertaken. Two advanced and two intermediate sprinters, each executing six trials of a 100-m dash, served as subjects. The results revealed that the power patterns for both the advanced and intermediate sprinters were similar in shape, depicting the same number of power phases. The hip joint musculature acted primarily as a power generator in comparison to the knee muscles, which acted mainly as absorbers (controllers) during the recovery phase of the sprinting stride. Differences between ability levels were identified using peak power values, with the advanced sprinters producing higher peak powers earlier in the recovery phase.

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Sander P.M. Ganzevles, Arnold de Haan, Peter J. Beek, Hein A.M. Daanen and Martin J. Truijens

For training to be optimal, daily training load has to be adapted to the momentary status of the individual athlete, which is often difficult to establish. Therefore, the current study investigated the predictive value of heart-rate recovery (HRR) during a standardized warm-up for training load. Training load was quantified by the variation in heart rate during standardized training in competitive swimmers. Eight female and 5 male Dutch national-level swimmers participated in the study. They all performed 3 sessions consisting of a 300-m warm-up test and a 10 × 100-m training protocol. Both protocols were swum in front crawl at individually standardized velocities derived from an incremental step test. Velocity was related to 75% and 85% heart-rate reserve (% HRres) for the warm-up and training, respectively. Relative HRR during the first 60 s after the warm-up (HRRw-up) and differences between the actual and intended heart rate for the warm-up and the training (ΔHRw-up and ΔHRtr) were determined. No significant relationship between HRRw-up and ΔHRtr was found (F 1,37 = 2.96, P = .09, R 2 = .07, SEE = 4.65). There was considerable daily variation in ΔHRtr at a given swimming velocity (73–93% HRres). ΔHRw-up and ΔHRtr were clearly related (F 1,37 = 74.31, P < .001, R 2 = .67, SEE = 2.78). HRR after a standardized warm-up does not predict heart rate during a directly subsequent and standardized training session. Instead, heart rate during the warm-up protocol seems a promising alternative for coaches to make daily individual-specific adjustments to training programs.

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Peter Peeling, Brian Dawson, Carmel Goodman, Grant Landers, Erwin T. Wiegerinck, Dorine W. Swinkels and Debbie Trinder

Urinary hepcidin, inflammation, and iron metabolism were examined during the 24 hr after exercise. Eight moderately trained athletes (6 men, 2 women) completed a 60-min running trial (15-min warm-up at 75–80% HRpeak + 45 min at 85–90% HRpeak) and a 60-min trial of seated rest in a randomized, crossover design. Venous blood and urine samples were collected pretrial, immediately posttrial, and at 3, 6, and 24 hr posttrial. Samples were analyzed for interleukin-6 (IL-6), C-reactive protein (CRP), serum iron, serum ferritin, and urinary hepcidin. The immediate postrun levels of IL-6 and 24-hr postrun levels of CRP were significantly increased from baseline (6.9 and 2.6 times greater, respectively) and when compared with the rest trial (p ≤ .05). Hepcidin levels in the run trial after 3, 6, and 24 hr of recovery were significantly greater (1.7–3.1 times) than the pre- and immediate postrun levels (p ≤ .05). This outcome was consistent in all participants, despite marked variation in the magnitude of rise. In addition, the 3-hr postrun levels of hepcidin were significantly greater than at 3 hr in the rest trial (3.0 times greater, p ≤ .05). Hepcidin levels continued to increase at 6 hr postrun but failed to significantly differ from the rest trial (p = .071), possibly because of diurnal influence. Finally, serum iron levels were significantly increased immediately postrun (1.3 times, p ≤ .05). The authors concluded that high-intensity exercise was responsible for a significant increase in hepcidin levels subsequent to a significant increase in IL-6 and serum iron.