Johnny Padulo

Kinematics Of Running At Different Slopes And Speeds

Abstract Padulo, J, Annino, G, Migliaccio, GM, DOttavio, S, and Tihanyi, J. Kinematics of running at different slopes and speeds. J Strength Cond Res 26(5): 1331–1339, 2012—The aim of this study was to verify the influence of the combination of different running speeds and slopes based on main kinematic parameters in both groups of elite (RE) and amateur (RA) marathon runners. All subjects performed various tests on a treadmill at 0, 2, and 7% slopes at different speeds: 3.89, 4.17, 4.44, 4.72, and 5.00 m·s−1. A high speed digital camera, 210 Hz, has been used to record; Dartfish 5.5Pro has been used to perform a 2D video analysis. Step length (SL), step frequency (SF), flight time (FT), and contact time (CT) were determined and used for comparison. SL, SF, and FT parameters increased, and CT parameter decreased as speed increased. As slopes increased, SL and FT decreased and SF increased in both groups and only CT decreased in RE, whereas in RA, it increased. Data were fitted to the linear regression line (R2 > 0.95). The 2 groups were significantly different (p < 0.05) in FT, SL, and SF at all speeds in level running. A significant difference between the 2 groups was found in FT at 2 and 7% slopes at all speeds (p < 0.05). Percentage alterations in all variables were greater in the RA group. In conclusion, the choice of optimum SL and SF, through efficient running can be maintained, is influenced not only by speed but also by slopes. Elite runners perform more efficiently than amateur runners who have less experience.

The acute effect of whole body vibration on repeated shuttle-running in young soccer players.

The aim of this study was to investigate the acute effects of whole-body vibration (WBV) on Repeated Sprint Ability (RSA). Seventeen male soccer players (16.71±0.47 y) performed three RSA tests (Randomized crossover study design). The second RSA test was done with WBV (RSA2) to assess the effect of WBV. The studied variables were: best time (BT), worst time (WT), total time (TT), the fatigue index (FI) of RSA, and post-test blood lactate (BLa). ANOVA with repeated measures showed no differences between RSA1 and RSA3, while there were significant differences in all variables studied. TT= [RSA2 0.93% and 1.68% lower than RSA1 and RSA3 respectively; p<0.05], BLa= [RSA2 16.97% and 14.73% greater than RSA1 and RSA3 respectively; p<0.001], WT= [RSA2 1.90% and 2.93% lower than RSA1 and RSA3 respectively; p<0.01], and FIu2009= [RSA2 30.64% and 40.15% lower than RSA1 and RSA3 respectively; p<0.0001]. When comparing individual sprints, WBV showed a significant effect at the 5th sprint: RSA2 2.29% and 2.95% lower than RSA1 and RSA3 respectively (p<0.005), while at the 6th sprint: RSA2 2.75% and 4.09% lower than RSA1 and RSA3 respectively; p<0.005. In conclusion, when applying WBV during the recovery periods of Repeated Sprint Ability efforts, most of the performance variables improved.

Uphill racewalking at iso-efficiency speed.

Abstract Padulo, J, Annino, G, Tihanyi, J, Calcagno, G, Vando, S, Smith, L, Vernillo, G, La Torre, A, and DOttavio, S. Uphill racewalking at iso-efficiency speed. J Strength Cond Res 27(7): 1964–1973, 2013—The aim of this study was to investigate the effects of gradients (0, 2, and 7%) on biomechanical parameters during racewalking (RW) at iso-efficiency speed (IES). During the experiment, 12 high-level athletes performed at IES on different slopes. The parameters studied were surface muscular activity (EMG) of 5 muscles of the leg using Muscle Lab (Boscosystem); kinematic parameters were collected using a high-speed camera (210 Hz) analyzed with Dartfish 5.5Pro; and heart rate (HR) was monitored with a Cardio Polar. The results showed step length (SL), step frequency (SF), and internal work (WINT) decreased with increased treadmill gradient: SL = ([0–2% = 3.48%, p = 0.158], [0–7% = 12.17%, p < 0.001]); SF = ([0–2% = 2.38%, p = 0.173], [0–7% = 6.07%, p < 0.01]); WINT = ([0–2% = 8.34%, p < 0.001], [0–7% = 22.81%, p < 0.0001]). Conversely, contact time (CT) and HR increased less significantly with the increased gradients: CT = ([0–2% = 2.46%, p = 0.198], [0–7% = 6.56%, p < 0.01]); HR = ([0–2% = 0.62%, p = 0.652], [0–7% = 3.25%, p < 0.05]). The knee angle (KE) increased, whereas ankle angle (AK) and hip angle (HP) decreased with the increased gradients: AK = ([0–2% = 1.69%, p < 0.001], [0–7% = 1.13%, p < 0.01]); HP = ([0–2% = 0.22%, p < 0.03], [0–7% = 0.16%, p = 0.456]); KE = ([0–2% = 1.01%, p < 0.001], [0–7% = 1.60%, p < 0.001]). Electromyography (EMG) significantly decreased with the increased gradients in the: tibialis anterior ([0–2% = 22.49%, p < 0.0001], [0–7% = 41.18%, p < 0.0001]) and rectus femoris ([0–2% = 15.35%, p < 0.0001], [0–7% = 29.13%, p< 0.0001]). In contrast, EMG activity was significantly increased in the vastus lateralis ([0–2% = 22.95%, p < 0.0001], [0–7% = 31.15%, p < 0.0001]), gastrocnemius medialis ([0–2% = 21.40%, p < 0.001], [0–7% = 48.37%, p < 0.0001]), and biceps femoris ([0–2% = 190.78%, p < 0.0001], [0–7% = 201.37%, p < 0.0001]). The results indicate that increasing the gradient to 2% did not elicit an increased HR in racewalkers; however, at a 7% gradient, greater muscle activity was required.

Footstep Manipulation during Uphill Running

The present study investigated the effects of step frequency manipulation during training on slopes (2%) on biomechanical parameters at Iso-Efficiency Speed (without increasing the metabolic demand). 24 male marathon runners were randomly allocated to one of 2 training groups for 3 weeks: step frequency manipulation group (SFM, n=12) and free step frequency group (SFF, n=12). Lower limb kinematic parameters were measured before and after the 3 weeks training. The SFM group increased step length 4.30% (p<0.001), flight time 29.48% (p<0.001) and decreased contact time 14% (p<0.01). These findings coincide with characteristics of better running performances. The SFF group did not elicit such results. The results from the study could help coaches to devise training methods which could improve an athletes performance through increasing step length. The method provided may aid faster race times for athletes.

The Impact of Jumping during Recovery on Repeated Sprint Ability in Young Soccer Players

This study compared the effect of counter-movement-jump (CMJ)-based recovery on repeated-sprint-ability (RSA). Eighteen male footballers (16 ± 0 years, 65 ± 10 kg, 1.74 ± 0.10 m) performed three RSA-tests. RSA-1/-3 were performed according to standard procedures, while three CMJs (over 10″) – as a potential fatigue-determinant and/or running mechanics interference – were administered during RSA-2 recoveries. RSA performance, exercise effort (fatigue index [FI], rating of perceived exertion [RPE], blood lactate concentration [BLa]), simple kinematics (steps number), vertical-jump characteristics (stretch-shortening-cycle-efficiency [SSCE] assessed before/after RSA) were investigated. ANOVA showed no differences between RSA-1,-3. During RSA-2, performance was lower than RSA-1/-3, while steps number did not change. During RSA-2, FI, BLa, RPE were higher than RSA-1/-3 (FI +21.10/+20.43%, P<0.05; BLa +16.25/+13.34%, P<0.05; RPE +12.50/+9.57%, P<0.05). During RSA-2, SSCE, as the CMJ/squat-jump-height-ratio, was not significantly different from RSA-1/-3. Passive recovery RSA allows better performance. Yet, RSA CMJ-based recovery is effective in increasing training load (FI, BLa, RPE) without perturbing running mechanics (simple kinematics, SSCE).

Evaluating BCI devices: a statistical perspective

To the Editor, Several letters on statistical procedures and scientific approaches entitled ‘Statistics: all together not’ (Hopkins et al. 2011a, 2011b, 2011c, 2011d) and ‘Concentric and eccentric: muscle contraction or exercise?’ (Padulo, Dal Pupo, et al. 2013; Padulo, Laffaye, Chamari, Concu 2013; Padulo, Laffaye, Ardigò, Chamari 2013) have been published in scientific journals between 2011 and 2013. These aim to encourage improved reporting of methodological procedures and correct usage of statistics in scientific articles. In 2012, a paper was published in Ergonomics, examining the potential use of consumer brain computer interface (BCI) devices for research and experimentation (Ekandem et al. 2012). Ekandem et al. describe BCI devices as ‘ . . . physical devices that allow one-way communication from the human brain to an external machine by interpreting electroencephalography brain wave data’. This is clearly an interesting and important area of research. We wish to argue, however, that evaluating the feasibility of using consumer BCIs within scientific research (or even as lie detector equipment) requires a more rigorous scientific approach and reporting of details. We do not believe that the paper provides sufficient information to support its reasoning and conclusions. The aim of this letter is to identify, in our opinion, important omissions and errors. The following points are intended to establish the scientific standard we consider to be essential with studies of the nature described by Ekandem et al. (2012):

Measurement errors when estimating the vertical jump height with flight time using photocell devices: the example of Optojump

Common methods to estimate vertical jump height (VJH) are based on the measurements of flight time (FT) or vertical reaction force. This study aimed to assess the measurement errors when estimating the VJH with flight time using photocell devices in comparison with the gold standard jump height measured by a force plate (FP). The second purpose was to determine the intrinsic reliability of the Optojump photoelectric cells in estimating VJH. For this aim, 20 subjects (age: 22.50±1.24 years) performed maximal vertical jumps in three modalities in randomized order: the squat jump (SJ), counter-movement jump (CMJ), and CMJ with arm swing (CMJarm). Each trial was simultaneously recorded by the FP and Optojump devices. High intra-class correlation coefficients (ICCs) for validity (0.98-0.99) and low limits of agreement (less than 1.4 cm) were found; even a systematic difference in jump height was consistently observed between FT and double integration of force methods (-31% to -27%; p<0.001) and a large effect size (Cohen’s d>1.2). Intra-session reliability of Optojump was excellent, with ICCs ranging from 0.98 to 0.99, low coefficients of variation (3.98%), and low standard errors of measurement (0.8 cm). It was concluded that there was a high correlation between the two methods to estimate the vertical jump height, but the FT method cannot replace the gold standard, due to the large systematic bias. According to our results, the equations of each of the three jump modalities were presented in order to obtain a better estimation of the jump height.

RETRACTED: Concentric and Eccentric Exercise

To the Editor: This contribution considers the use and possiblemisuse of the terms concentric and eccentric in several contexts: first, the origin of terms; second, different approaches; and third, the possible uses. To our knowledge, an article has been published in The Journal of Pain misusing the terms concentric/eccentric exercise. The purpose of this letter is to foster the use of the terminology positive/negative work together with concentric/ eccentric contraction to ease reference search (ie, through key words) and comprehension.

Wii Balance Board as a device for investigating kayak’sbiomechanics: a pilot study

SISMES VI NATIONAL CONGRESS Naples, 26–28 September 2014 The Marcello Faina Lecture Fitness and health effects of recreational football for untrained individuals across the life span