Validity and Reliability of a New Specific Parkour Test : Physiological and Performance Responses

Main aim of this study was examining validity and reliability of using a new specific Parkour repeated sprint ability test (SPRSA) for assessing repeated sprint ability while facing obstacles and establishing between-day reliability and sensitivity of SPRSA related to its physiological and performance responses. Thirteen high-level traceurs (three females) performed in random order and twice eight tests for assessing a total of 23 variables: SPRSA (a typical maximal-speed shuttle run interspersed with four Parkour competition-common fundamentals) and seven established fitness tests, core stability, hand-grip, vertical-jump, long-jump, pull-up, 300-m shuttle run (as a field test for anaerobic capacity), and Leger test. Except for muscular elasticity index of vertical jump test (intra-class Correlation Coefficient model 3,1 [ICC3,1] = 0.54 [fair]), fitness tests' ICC3,1s resulted excellent (ICC3,1: 0.93-1.00). SPRSA total time and time of its fastest sprint (SPRSA peak time) were significantly correlated with the majority of core stability (r: -0.79 to 0.59; P < 0.01-0.05), jumping (r: -0.78 to 0.67; P < 0.01-0.05), pull-up tests (r: -0.86; P < 0.01), 300-m shuttle run test total time (r: 0.77-0.82; P < 0.01), and Leger test-estimated VO2 max (r: -0.78; P < 0.01). Principal component analysis (PCA) of the 23 variables led to extraction of four significant components (each due to different variables' combinations), which explained 90.2% of 23 variables' total variance. SPRSA (i.e., total and peak time) showed high reliability (ICC3,1: 0.991-0.998 and standard-error-of-measurement %: 0.07-0.32). Finally, SPRSA showed high sensitivity (smallest-worthwhile-change %: 0.29-0.68). Considering its excellent logical and strong ecological validity, SPRSA may serve as a valid specific field test for Parkour sport. In addition, thanks to its high reliability and sensitivity, this test is suitable for monitoring, evaluating, and programming training processes for Parkour practitioners in repeated sprint ability involving crossing obstacles

External Responsiveness of the SuperOpTM Device to Assess Recovery After Exercise : A Pilot Study

Post-exercise recovery is a complex process involving a return of performance and a physiological or perceptual feeling close to pre-exercise status. The hypothesis of this study is that the device investigated here is effective in evaluating the recovery state of professional cyclists in order to plan effective training. Ten professional male cyclists belonging to the same team were enrolled in this study. Participants performed a 7-day exercise program [D1, D4, and D7: low-intensity training; D2 and D5: passive recovery; D3: maximum oxygen consumption (VO2Max) test (for maximum mechanical power assessment only); and D6: constant load test]. During the week of monitoring, each morning before getting up, the device assessed each participant's so-called Organic Readiness {OR [arbitrary unit (a.u.)]}, based on blood pressure (BP), heart rate (HR), features of past exercise session, and following self-perceived condition. Based on its readings and algorithm, the device graphically displayed four different colors/values, indicating general exercise recommendations: green/3 = \u201cyou can train hard,\u201d yellow/2 = \u201cyou can train averagely,\u201d orange/1 = \u201cyou can train lightly,\u201d or red/0 = \u201cyou should recover passively.\u201d During the week of research, morning OR values and Bonferroni post-hoc comparisons showed significant differences between days and, namely, values (1) D2 (after low intensity training) was higher than D4 (after VO2Max test; P = 0.033 and d = 1.296) and (2) D3 and D6 (after passive recovery) were higher than D4 (after VO2Max test; P = 0.006 and d = 2.519) and D5 (after low intensity training; P = 0.033 and d = 1.341). The receiver operating characteristic analysis area under curve (AUC) recorded a result of 0.727 and could differentiate between D3 and D4 with a sensitivity and a specificity of 80%. Preliminarily, the device investigated is a sufficiently effective and sensitive/specific device to assess the recovery state of athletes in order to plan effective training

The Effect of Heart Rate on Jump-Shot Accuracy of Adolescent Basketball Players

Basketball is a team sport, where fundamental skills - fundamentals - are key determinants for success. Jump-shot (JS) is a basketball fundamental used frequently during game. It is interesting to spread light on the relationship between effort intensity and JS ability. Study aim was to investigate different heart rates (HRs) effect on JS accuracy (JS%) in 22 male youth (15.7 +/- 0.9 years) players. Experimental sessions consisted of 10 JSs from five spots 5 m from basket at three different HRs: rest (0HR) and after warm-up (50% [50HR] and 80% maximal HR [80HR]). Analysis of variance showed differences in JS% over sessions (42.27 +/- 14.78% at 0HR, 38.18 +/- 10.53% at 50HR, and 30.00 +/- 16.62% at 80HR; P = 0.018). Least significant difference test did not show any significant difference between 50HR and 0HR JS% (P = 0.343), while 80HR elicited significantly lower values with respect to both 0HR (P = 0.006) and 50HR (P = 0.049). Study provided practical indications on maintaining high JS%: preliminary warm-up (even if injury-protecting) does not improve JS%, because between 50HR and 0HR difference was not significant; and 80HR significantly decreases JS%. Therefore, to maximize JS scoring players have to rest as much as possible during game-play pauses, and coaches should manage timeouts and substitutions accordingly, especially during final minutes of close games

Halteres used in ancient Olympic long jump

Halteres are hand-held weights that were first used in the standing long jump in the eighteenth ancient Olympiad in 708 bc, and may have been introduced either to make the challenge more difficult or to extend the jumping distance. Here we use computer and experimental simulations to determine the optimal mass of halteres that would be needed to maximally extend a standing long jump, and find that this corresponds closely to the size range of actual archaeological specimens. These halteres were made of stone or lead and weighed 2 129 kg, which we calculate would increase a 3-metre jump by at least 17 cm, indicating that their purpose was to boost the performance of pentathletes. Halteres may therefore be the earliest passive tool that was devised to enhance human-powered locomotion

Measured and predicted mechanical internal work in human locomotion

Predictive methods estimating mechanical internal work (Wint, i.e., work to accelerate limbs with respect to BCOM during locomotion) are needed in absence of experimental measurements. A previously proposed model equation predicts such a parameter based upon velocity, stride frequency, duty factor, and a compound critical term (q) accounting for limb geometry and inertial properties. That first predicted Wint estimate (PWint) has been validated only for young males and for a limited number of horses. The present study aimed to extend the comparison between model predictions and experimentally measured Wint (MWint) data on humans with varying gender, age, gait, velocity, and gradient. Seventy healthy subjects (males and females; 7 age groups: 6-65years) carried out level walking and running on treadmill, at different velocities. Moreover, one of the subject groups (25-35years) walked and ran also at several uphill/downhill gradients. Reference values of q represent the main important results: (a) males and females have similar q values; (b) q is independent on velocity and gradient. Also, different data filtering depth was found to affect MWint and, indirectly, PWint, thus also the reference q values here obtained (0.08 in level, 0.10 in gradient) suffer a - 20% underestimation with respect to the previous predicting model. Despite of this effect, the close match between MWint and PWint trends indicates that the model equation could be satisfactorily applied, in various locomotion conditions

Mechanical determinants of the minimum energy cost of gradient running in humans

The metabolic cost and the mechanical work of running at different speeds and gradients were measured on five human subjects. The mechanical work was partitioned into the internal work (Wint) due to the speed changes of body segments with respect to the body centre of mass and the external work (Wext) due to the position and speed changes of the body centre of mass in the environment. Wext was further divided into a positive part (W+ext) and a negative part (W-ext), associated with the energy increases and decreases, respectively, over the stride period. For all constant speeds, the most economical gradient was -10.6 +/-0.5% (S.D., N = 5) with a metabolic cost of 146.8 +/- 3.8 ml O2 kg-1 km-1. At each gradient, there was a unique W+ext/W-ext ratio (which was 1 in level running), irrespective of speed, with a tendency for W-ext and W+ext to disappear above a gradient of +30% and below a gradient of -30%, respectively. Wint was constant within each speed from a gradient of -15% to level running. This was the result of a nearly constant stride frequency at all negative gradients. The constancy of Wint within this gradient range implies that Wint has no role in determining the optimum gradient. The metabolic cost C was predicted from the mechanical experimental data according to the following equation: [formula: see text] where eff- (0.80), eff+ (0.18) and effi (0.30) are the efficiencies of W-ext, W+ext and Wint, respectively, and el- and el+ represent the amounts of stored and released elastic energy, which are assumed to be 55J step-1. The predicted C versus gradient curve coincides with the curve obtained from metabolic measurements. We conclude that W+ext/W-ext partitioning and the eff+/eff- ratio, i.e. the different efficiency of the muscles during acceleration and braking, explain the metabolic optimum gradient for running of about -10%

The optimal locomotion on gradients : walking, running or cycling?

On level ground, cycling is more economical than running, which in turn is more economical than walking in the high speed range. This paper investigates whether this ranking still holds when moving on a gradient, where the three modes are expected to be mainly facing the same burden, i.e. to counter gravity. By using data from the literature we have built a theoretical framework to predict the optimal mode as a function of the gradient. Cycling was found to be the mode of choice only below 10\u201315% gradient, while above it walking was the least expensive locomotion type. Seven amateur bikers were then asked to walk, run and ride on a treadmill at different gradients. The speed was set so as to maintain almost constant the metabolic demand across the different gradients. The results indicate that the "critical slope", i.e. the one above which walking is less expensive than cycling (and running), is about 13\u201315%. One subject was loaded during bipedal gaits with a bicycle-equivalent mass, to simulate to cross-country cycling situation. The critical slope was close to 20%, due to the higher metabolic cost of loaded walking and running. Part of the findings can be explained by the mechanically different paradigms of the three locomotion types

Keystroke dynamics and timing : accuracy, precision and difference between hands in pianist\u2019s performance

A commercially available acoustic grand piano, originally provided with keystroke speed sensors, is proposed as a standard instrument to quantitatively assess the technical side of pianist's performance, after the mechanical characteristics of the keyboard have been measured. We found a positional dependence of the relationship between the applied force and the resulting downstroke speed (i.e. treble keys descend fastest) due to the different hammer/hammer shaft mass to be accelerated. When this effect was removed by a custom software, the ability of 14 pianists was analysed in terms of variability in stroke intervals and keystroke speeds. C-major scales played by separate hands at different imposed tempos and at 5 subjectively chosen graded force levels were analysed to get insights into the achieved neuromuscular control. Accuracy and precision of time intervals and descent velocity of keystrokes were obtained by processing the generated MIDI files. The results quantitatively show: the difference between hands, the trade off between force range and tempo, and between time interval precision and tempo, the lower precision of descent speed associated to 'soft' playing, etc. Those results reflect well-established physiological and motor control characteristics of our movement system. Apart from revealing fundamental aspects of pianism, the proposed method could be used as a standard tool also for ergonomic (e.g. the mechanical work and power of playing), didactic and rehabilitation monitoring of pianists