Active recovery of the finger flexors enhances intermittent handgrip performance in rock climbers

This study aimed to (1) evaluate the effect of hand shaking during recovery phases of intermittent testing on the time–force characteristics of performance and muscle oxygenation, and (2) assess inter-individual variability in the time to achieve the target force during intermittent testing in rock climbers. Twenty-two participants undertook three finger flexor endurance tests at 60% of their maximal voluntary contraction until failure. Performances of a sustained contraction and two intermittent contractions, each with different recovery strategies, were analysed by time–force parameters and near-infrared spectroscopy. Recovery with shaking of the forearm beside the body led to a significantly greater intermittent test time (↑ 22%, P < .05), force–time integral (↑ 28%, P < .05) and faster muscle re-oxygenation (↑ 32%, P < .05), when compared to the hand over hold condition. Further, the ratio of intermittent to continuous test time distinguished specific aerobic muscular adaptations among sport climbers (2.02), boulderers (1.74) and lower grade climbers (1.25). Lower grade climbers and boulderers produced shorter duration contractions due to the slower development of target force during the intermittent test, indicating worse kinaesthetic differentiation. Both the type of recovery and climbing discipline determined muscle re-oxygenation and intermittent performance in rock climbers

New Zealand blackcurrant extract enhances muscle oxygenation during repeated intermittent forearm muscle contractions in advanced and elite rock climbers

Anthocyanin-rich New Zealand blackcurrant (NZBC) may improve forearm muscle oxygenation and enhance performance in high-level rock climbers. As such, using a double-blind, randomized, cross-over design study, twelve participants performed an oxidative capacity assessment, and two successive exhaustive exercise trials (submaximal forearm muscle contractions at 60 % of their maximal volitional contraction). Each visit was conducted following 7-days intake of 600 mg·day-1 NZBC extract or placebo. Oxidative capacity was estimated by calculating the oxygen half time recovery using near infrared spectroscopy. Time to exhaustion (s), impulse (kg·s), and minimum tissue saturation index (min-TSI %) were assessed during both the exercise trials. Muscle oxidative capacity was greater with NZBC (mean difference [MD] = 5.3 s, 95% confidence intervals [95% CI] = 0.4 – 10.2 s; p = 0.036; Cohen’s d = 0.94). During the exercise trials, there was an interaction for min-TSI % (time x condition, p = 0.046; ηp2 = 0.372), which indicated a greater level of oxygen extraction during trial two with NZBC extract (MD = 9 %, 95% CI = 2-15 %) compared to the placebo (MD = 2 %, 95% CI = 1 - 7 %). There was a decrease in time to exhaustion (p <0.001, ηp2 =0.693) and impulse (p = 0.001, ηp2 =0.672) in exercise trial two, with no effect of NZBC extract. In high level rock climbers 7-days NZBC extract improves forearm muscle oxygenation with no effect on isolated forearm muscle performance

Forearm muscle oxidative capacity index predicts sport rock-climbing performance

Abstract: Rock-climbing performance is largely dependent on the endurance of the forearm flexors. Recently, it was reported that forearm flexor endurance in elite climbers is independent of the ability to regulate conduit artery (brachial) blood flow, suggesting that endurance is not primarily dependent on the ability of the brachial artery to deliver oxygen, but rather the ability of the muscle to perfuse and use oxygen, i.e., skeletal muscle oxidative capacity. Purpose: The aim of the study was to determine whether an index of oxidative capacity in the flexor digitorum profundus (FDP) predicts the best sport climbing red-point grade within the last 6 months. Participants consisted of 46 sport climbers with a range of abilities. Methods: Using near-infrared spectroscopy, the oxidative capacity index of the FDP was assessed by calculating the half-time for tissue oxygen resaturation (O2HTR) following 3–5 min of ischemia. Results: Linear regression, adjusted for age, sex, BMI, and training experience, revealed a 1-s decrease in O2HTR was associated with an increase in red-point grade by 0.65 (95 % CI 0.35–0.94, Adj R2 = 0.53). Conclusions: Considering a grade of 0.4 separated the top four competitors in the 2015 International Federation Sport Climbing World Cup, this finding suggests that forearm flexor oxidative capacity index is an important determinant of rock-climbing performance

Differences in forearm strength, endurance, and hemodynamic kinetics between male boulderers and lead rock climbers

This study examined differences in the oxygenation kinetics and strength and endurance characteristics of boulderers and lead sport climbers. Using near infrared spectroscopy, 13-boulderers, 10-lead climbers, and 10-controls completed assessments of oxidative capacity index and muscle oxygen consumption (mV̇O2) in the flexor digitorum profundus (FDP), and extensor digitorum communis (EDC). Additionally, forearm strength (maximal volitional contraction MVC), endurance (force–time integral FTI at 40% MVC), and forearm volume (FAV and ΔFAV) was assessed. MVC was significantly greater in boulderers compared to lead climbers (mean difference = 9.6, 95% CI 5.2–14 kg). FDP and EDC oxidative capacity indexes were significantly greater (p = .041 and .013, respectively) in lead climbers and boulderers compared to controls (mean difference = −1.166, 95% CI (−3.264 to 0.931 s) and mean difference = −1.120, 95% CI (−3.316 to 1.075 s), respectively) with no differences between climbing disciplines. Climbers had a significantly greater FTI compared to controls (mean difference = 2205, 95% CI= 1114–3296 and mean difference = 1716, 95% CI = 553–2880, respectively) but not between disciplines. There were no significant group differences in ΔFAV or mV̇O2. The greater MVC in boulderers may be due to neural adaptation and not hypertrophy. A greater oxidative capacity index in both climbing groups suggests that irrespective of climbing discipline, trainers, coaches, and practitioners should consider forearm specific aerobic training to aid performance.N/

The Reliability of Parkour Skills Assessment

The aim of the study was to determine the reliability of parkour skills assessment in field conditions. Twenty young men completed three trials of a parkour obstacle course on two separate days. The tested group consisted of 10 beginners (age 16 ± 1 years, body mass = 65 ± 12 kg, height = 177 ± 7 cm) and 10 advanced traceurs (age 18 ± 2 years, body mass = 68 ± 14 kg, height = 178 ± 6 cm). The performance was video-recorded and subsequently analyzed by three raters (total score 0–45). Median and percentiles were used to characterize results from all sessions by all raters. Inter-rater, intra-session and inter-session reliability were assessed using Krippendorff’s α for ordinal data. The Mann-Whitney test was used to assess the differences between beginners and advanced traceurs. Advanced traceurs obtained a total score from 41 to 44 whilst beginners achieved 27 to 33 points. Krippendorff’s α for total score ranged from 0.910 to 0.916 between raters, 0.828 to 0.874 between trials, and from 0.839 to 0.924 between days. The proposed parkour course differentiated two different ability levels and the skills assessment demonstrated excellent reliability between raters, trials, and days

Effects of brassinosteroid application on seed germination of Norway spruce, Scots pine, Douglas fir and English oak

We tested the influence of a synthetically-produced brassinosteroid compound (2α,3α,17βtrihydroxy-5α-androstan-6-one) on seed germination in Norway spruce, Scots pine, Douglas fir and English oak. Before germination, 400 seeds of each species were steeped in a brassinosteroid solution and then placed for germination in a growth chamber under (i) optimal humidity and (ii) temporary drought stress (except for oak). Drought stress significantly reduced the germination capacity and germination rate in the control treatments of Norway spruce, Scots pine and Douglas fir. Nonetheless, the application of brassinosteroid significantly reduced the drought-stress effects in seeds of Norway spruce and Scots pine. The drought-stressed Douglas fir did not respond positively to the brassinosteroid application. English oak was germinated only under the optimal humidity regime and no differences in germination were detected between the control and brassinosteroid-treated acorns

The Relationship between Climbing Ability and Physiological Responses to Rock Climbing

Aim. The aim of this study was to examine the relationship between submaximal and maximal physiological responses to rock climbing for climbers of differing abilities. Methods. Twenty-six male climbers performed a submaximal climbing test on a known circuit at 90° (vertical) and 105° (15° overhanging) inclination and speed 25 movements·min−1. A maximal test was undertaken on a similar circuit at the same speed with inclination increasing by 10° for each successive 3 min stage. Results. Mean oxygen consumption and heart rate (HR) increased with wall inclination and climbers reached a mean (±SD) peak V˙O2 of 40.3 ± 3.5 mL·kg−1·min−1 during the maximal test. Self-reported climbing ability was negatively correlated with V˙O2 and HR during the submaximal test at 90° (V˙O2, r=−0.82; HR, and r=−0.66) and at 105° (V˙O2, r=−0.84; HR, and r=−0.78) suggesting an increased exercise economy for climbers with a higher ability level. Conclusion. Findings from this study indicate that there is a relationship between wall inclination and the physiological demand of a climb. However, the increased technical ability and fitness of higher level climbers appears to an extent to offset the increased demand through improved exercise economy which in turn leads to an increased time to exhaustion and an improvement in performance