The Role of Visual Feedback on Power Output During Intermittent Wingate Testing in Ice Hockey Players

Relationship between body composition and anaerobic power with inter-limb difference dependence in Czech elite ice hockey players

BACKGROUND

Ice hockey includes symmetrical as well as asymmetrical movements. As such, possible difference in mass and strength, as well as performance variables, may be observed between limbs.

METHODS

We examined the relation between body composition and lower extremity anaerobic power in Czech elite ice hockey players with the inter-limb difference dependence. In total, 168 ice hockey players (age = 20.81, Q1 = 18.24, Q3 = 28.75) underwent body composition measurement and Wingate Anaerobic Test (WAnT). The dominant (D) and non-dominant (ND) leg was established. A Wilcoxon Signed Rank was used. The difference between the dominant and non-dominant lower extremities was evaluated using the dimensionless analysis and by setting the value for the dominant leg at 100%.

RESULTS

The difference in muscle mass (MM), fat mass (FM), and WAnT outcome variables (MP, RAP, MP5sP) between the right and left leg was greater than the difference between D and ND leg. Less total body fat mass (TBFM) and more total body muscle mass (TBMM) and lower extremities muscle mass (LEMM) were associated with higher WAnT outcome values. The dimensionless analysis showed a statistically significant correlation between almost all variables.

CONCLUSIONS

More TBMF and LEMM and less TBFM was better for WAnT. The difference between the right and left leg was greater than the difference between D and ND leg. If there is a difference between MM and FM of lower limbs than there could be difference between the power of lower limbs as well.

Relationship between vertical jump tests and ice skating performance in junior Polish ice hockey players

The aim of this study was to determine the relationships between vertical jumps (VJ) and various on-ice skating performances of junior ice hockey players (n = 19). The three modes of VJ or off-ice measures were countermovement jump with arm swing (CMJ), squat jump (SJ) and depth drop jump (DDJ). The on-ice skating performance was measured by the skating multistage aerobic test (SMAT), forward and backward acceleration test, top speed test, and repeated sprint ability (RSA) test. The relationships between the variables were quantified using Pearson's product-moment correlation. DDJ showed a significant positive correlation with forward average skating speed (FASS) (r = 0.62) and strong correlations with backward average skating speed (BASS) (r = 0.81), and maximum skating speed (MSS) (r = 0.71). SJ was found to be strongly correlated with BASS (r = 0.82) and MSS (r = 0.76), whereas the only on-ice performance that significantly correlated with CMJ was BASS (r = 0.68). All three modes of VJ were inversely and non-significantly correlated with performance decrement index and fatigue index, as determined by the RSA test. SMAT was not significantly correlated with either VJ or RSA. Correlations between all three modes of VJ tests were significant. Therefore, this study concludes that: (1) DDJ can be used as a predictor of all the ice skating speed tests, whereas SJ can predict BASS and MSS. CMJ, on the other hand, can predict the performance of only BASS. (2) RSA performance cannot be predicted from CMJ, SJ, or DDJ tests, and (3) neither any of the VJ nor RSA can predict skating endurance of junior ice hockey players.

Warm up with music and visual feedback can effect Wingate performance in futsal players

PURPOSE

Visual feedback and music while warm up may help elicit peak performance, but its effect during the Wingate anaerobic test (WAnT) in futsal players is unexplored. Therefore, the aim of this study was to examine the effects of music and visual stimulus on WAnT performance in futsal players.

METHODS

The study included 17 young male futsal players (age, 21.53 ± 1.32 years; height, 177.59 ± 5.75 cm; 73.71 ± 9.31 kg; BMI 23.342 ± .47). The WAnT was administered using three distinct protocols: with music (M), without music (NM), and with music and visual feedback (MV) following a 10-min warm-up at 72-h intervals. After WAnT, the following parameters were evaluated: (a) peak power output: PPO (W), (b) relative peak power output: RPPO (W/kg), (c) mean power output: MPO (W), (d) relative mean power output: RMPO (W/kg), (e) fatigue index: FI (%), and (f) minimum power output MIPO (W).

RESULTS

MV indicated that futsal players' WAnT values, including PPO, RPPO, MPO, RMPO, and MIPO improved more than with other protocols (p < 0.05). However, there was no significant difference between protocols for FI (%) WAnT values (p > 0.05).

CONCLUSIONS

Listening to music and watching visual feedback while warm up before performing WAnT performance suggest to coaches and futsal players.

Effect of Real-Time Feedback on Power Output Using a Novel Smart-Resisted Sled Push

Prior studies have demonstrated the beneficial effects of real-time data feedback (RTF) on athletic performance and motivation. Despite this evidence, the lack of practical means to implement RTF has hindered its widespread adoption. Recently, a smart-resisted sled push was developed to improve athletic power by utilizing electromagnetic motors as a resistance mechanism, coupled with an RTF display. Thirty healthy college-aged male football players were recruited in this randomized, crossover designed study to examine the efficacy of the RTF to improve power output. Participants were randomized into either group 1 (receiving RTF first then no RTF) or group 2 (receiving no RTF first then RTF) during six, 10-meter sled pushes with 3 min rest intervals. The first three pushes were set to an easier level (L1) and the last three were set to a resistance level twice that of the first three runs (L2). A one-month washout period was enforced. For trials 1-3 (L1) (p = 0.026, t = -2.34, ES = -0.428) and 4-6 (L2) (p = 0.035, t = -2.22, ES = -0.405), peak power output (the average peak power output over the course of trials 1-3 and 4-6) was greater in both groups when receiving RTF compared to no-RTF. These findings demonstrate the effectiveness of RTF in augmenting power output during performance training.

Cadence Feedback and Video-Based Engagement Improves Motivation and Performance during Pedalling in Stroke Patients

Video and music as a dissociative attention stimulus during exercise is known to distract from the discomfort of physical exertion and improve exercise adherence; however, the influence of video-based feedback and engagement during pedalling on the performance and motivation of pedalling in stroke patients is poorly understood. The aim of this study was to employ a novel video-based engagement paradigm for pedalling in stroke patients and evaluate its capacity to influence the cadence control, physiological output, and perceived motivation and enjoyment. Thirteen stroke patients were recruited with low-to-moderate lower-limb disability (mean age: 64.0 yrs.). A reference group of 18 healthy young adult subjects (mean age: 27.7 yrs.) was also recruited to assess the broad applicability of the techniques to a contrasting non-pathological cohort. The participants pedalled at a slow (60 RPM) and fast (100 RPM) target speed with constant resistance in 15 min pedalling bouts that included (i) baseline pedalling with real-time visual feedback of cadence deviation from the target provided only in the first 20 s (ii) real-time visual feedback of cadence data over the entire pedalling session, and (iii) real-time engagement to maintain the playback rate of a prerecorded video by pedalling at the target speed. During low speed pedalling, stroke patients demonstrated significantly smaller absolute cadence deviation during pedalling with feedback (mean difference: 1.8 RPM, p = 0.014) and video-based engagement (mean difference: 2.4 RPM, p = 0.006) compared to the baseline pedalling. For the healthy adults, feedback and video-based engagement reduced cadence deviation significantly at all speeds (p < 0.05). All but one stroke patient either enjoyed or really enjoyed the video engagement during pedalling and felt motivated to undertake this form of exercise in therapy in the future. This proof-of-concept study showed that feedback and video-based engagement may improve the targeted pedalling performance in stroke patients, and by helping dissociate subjects from physical cues associated with fatigue, may ultimately improve exercise motivation and compliance.

Effects of Knowledge of Results and Change-Oriented Feedback on Swimming Performance

PURPOSE

This study examined the effect of providing knowledge of results (KR) with, and without, promotion- and change-oriented feedback on repeated-sprint ability in swimmers.

METHODS

Twenty-nine male and female swimmers (age = 16 [1] y, height = 1.74 [0.07] m, body mass = 61.0 [8.4] kg) were randomly allocated into 2 different feedback conditions, or a condition without feedback (NoFb), as a crossover, repeated-measures design. In one feedback condition, the swimmers were provided with lap completion times as KR. The other feedback condition was athlete-driven, where the swimmers were asked to estimate their lap completion times, and the investigators responded on whether their actual sprint times were faster (promotion-oriented), slower (change-oriented), or the same.

RESULTS

The results showed significantly faster average completion times during the repeated-sprint swim protocol in the athlete-driven KR (P = .014) and KR condition (P = .023), when compared with the NoFb condition. However, significantly faster best completion time was only found in the KR condition (P = .012), when compared with the NoFb condition. Furthermore, the stroke rate was significantly greater during the athlete-driven KR (P = .009) and KR (P = .021) conditions, when compared with the NoFb condition.

CONCLUSIONS

The KR condition exhibited the greatest benefit for improving several swimming performance measures during a repeated-sprint protocol, and the increase in stroke rate may have contributed to this performance enhancement. Thus, it is recommended that swimmers receive lap completion times during repeated-sprint training sessions to optimize training quality.

The Effect of Real-Time Video-Based Engagement and Feedback during Pedaling on Cadence Control and Exercise Motivation: A Proof-of-Concept Study

The use of video and music as an intrinsic, dissociative attentional stimulus during exercise is thought to distract from the physical discomfort of exercise, and contribute to improved exercise adherence; however, the effects of video-based feedback and engagement during pedaling on exercise performance and motivation are poorly understood. The aims of the present study were twofold. Firstly, to develop a novel video-based engagement regime for pedaling that links pedaling cadence with the play rate of a video, and secondly, to employ an instrumented pedaling device to assess the influence of the video engagement paradigm on cadence performance and exercise motivation. Eighteen healthy subjects participated in 15-min-duration pedaling sessions while targeting a specific low cadence (60 rotations per minute) and high cadence (100 rotations per minute), including pedaling with the provision of (i) target pedaling cadence information only, (ii) visual feedback on cadence control, including pedaling duration, pedaling cadence, and cadence deviation from target, and (iii) real-time engagement, which involved pedaling at the target speed to maintain the playback rate of a pre-recorded video. Cadence deviation from the target was evaluated, and self-reported exercise motivation examined with a post-exercise survey. Pedaling-cadence deviations significantly reduced with cadence feedback at both low and high cadence (p < 0.05). Participants reported enjoying feedback and video-based engagement during pedaling, with 83% of participants feeling that engagement motivated them to perform pedaling-based exercise. In conclusion, real-time cadence control feedback and video-based engagement during pedaling for healthy individuals may improve performance in targeted pedaling tasks. Through dissociation from the physical cues associated with exercise and fatigue, feedback and engagement may ultimately increase enjoyment and exercise compliance and adherence of pedaling-based exercise. The findings may be useful in prescription and maintenance of targeted pedaling exercises for stroke rehabilitation and exercise therapy.

Familiarization and Reliability of the Isometric Knee Extension Test for Rapid Force Production Assessment

Despite the rising interest in the use of portable force sensors during isometric exercises to inform on neuromuscular performance, the design of practical field-based methods to obtain reliable measures is an ongoing challenge. We aim at identifying the intra-session and test-retest reliability of a rapid, isometric knee extension test to evaluate the maximal voluntary concentric force (MVC), rate of force development (RFD) and impulse following a field-based approach. On two occasions, 14 athletes unfamiliar with the test completed three sets of 2 s ballistic contractions (as fast and hard as possible) with 30 s rest. Raw and filtered data were collected in real time using a portable force sensor. RFD and impulse were highly reliability during “late” phases of the contraction (0–250 ms) since the first session (coefficient of variation (CV) < 9.8%). Earlier phases (0–150 ms) achieved a moderate reliability after one familiarization session (CV < 7.1%). Measures at 0–50 ms did not reach sufficient reliability (CV~14%). MVC was accurately assessed. Dominant limbs were not importantly altered by the familiarization. In opposite, non-dominant limbs showed large variations. New evidence is provided about the positive effects of a single familiarization session to improve the reliability the isometric knee extension test for rapid force production assessment. Coaches and practitioners may benefit of from these findings to conduct practical and reliable assessments of the rapid force production using a portable force sensor and a field-based approach.

A Review of Players' Characterization and Game Performance on Male Rink-Hockey

The aim of this study was to review the evolutionary tendencies of research regarding to the study of male Rink-Hockey players´ and game performance. A systematic search was conducted in PubMed, Web of Knowledge and Scopus databases according to PRISMA method. The initial search identified 815 titles, resulting in 19 articles being included within the review. Original papers (English language) contained relevant data regarding rink hockey players' performance or morphological/physiological demands, anthropometry/body composition characteristics were eligible. Studies were classified into categories: (1) Physiological Demands, (2) Anthropometry and Body Composition, (3) Game Characterization/Patterns, (4) Injuries. Results indicated that Rink hockey requires high intensity effort which demands both short and long duration efforts requirements from players. Body composition analysis shows to be an important monitoring tool which complements the understanding of the athlete's cardiac adaptation. Game patterns shows a combination of specific game momentums with different outcomes according to the game zone. The intense short-term movements, collision and contact between players, in addition to the weight and speed of the hard ball and the stick, can considerably increase the risk of moderate and severe injuries. Lack of literature in Rink-Hockey is remarkable, and research is mainly focused on children and adolescents' players. Furthermore, the existing research with adult elite athletes was assessed with a small sample size.

Changes of Differential Urinary Metabolites after High-Intensive Training in Teenage Football Players

Objective

The mechanism underlying the fatigue of football players is closely related to the energy depletion and accumulation of metabolites; the present study tries to explore the metabolic mechanism in teenage football players during exercise-induced fatigue.

Methods

12 teenage football players were subjected to three groups of combined training by using a cycle ergometer, with the subjective Rating of Perceived Exertion (RPE) as a fatigue criterion. The following indicators were measured in each group after training: maximum oxygen uptake (VO_2max), anaerobic power, and average anaerobic power. Urine samples were collected before and after the training. Gas chromatography-mass spectrometry (GC-MS) was performed for the metabonomics analysis of the samples. The metabolism data was analyzed by using principal component analysis (PCA) and orthogonal partial least squares analysis (OPLS-DA), through the Kyoto Encyclopedia of Genes and Genomes (KEGG) database to confirm the potential differences between metabolites, and the MetPA database was used to analyze the related metabolic pathways.

Results

There was no significant difference between the maximal oxygen uptakes among the three groups. Compared with group 1, the maximum and average anaerobic power in group 3 significantly decreased (p < 0.05) at the end of training. GC-MS detected 635 metabolites in the urine samples. Through PCA, OPLS-DA analysis, and KEGG matching, 25 different metabolites (3↑22↓) that met the conditions were finally selected. These different metabolites belonged to 5 metabolic pathways: glycine-serine-threonine metabolism, citrate cycle, tyrosine metabolism, nitrogen metabolism, and glycerophospholipid metabolism.

Conclusions

During the combined exercise of aerobic and anaerobic metabolism, teenage football players show a significant decrease in anaerobic capacity after fatigue. The metabolic mechanism of exercise fatigue was related to disorders in amino acid and energy metabolism.

Off-Ice Agility Provide Motor Transfer to On-Ice Skating Performance and Agility in Adolescent Ice Hockey Players

Agility plays a crucial role in ice hockey training, and it can be developed directly on the ice or by additional off-ice training. Since the effectiveness of on-ice and off-ice training on players' agility have not been previously described, the purpose of this research is to compare the effects of on-ice and off-ice agility training on skating performance. Fourteen ice hockey players performed agility training on-ice for 4 weeks and off-ice for 4 weeks in a crossover design; they were tested before the agility program, after the first month and after finishing both training programs. The players were randomly assigned into one of two groups (n = 7 in each group), either performing the on-ice training protocol first (Ice1) followed by the off-ice agility training or performing the off-ice protocol first and the on-ice training second (Ice2). The test battery included straight sprints to 6.1 m and 35 m and the S corner test, test with break, weave agility with puck test and reactive agility test. The magnitude based decision showed the effect of agility training in both groups in the weave agility (Ice1, 2.9±2.8% likely improvement; Ice2, 3.1±2.5% possible improvement) and reactive agility tests (Ice1, 3.1 ±2.5% likely improvement; Ice2, 1.7±2.1% possible improvement), where the Ice1 protocol resulted in a likely positive change and Ice2 resulted in a possible positive change. The comparison of the training effect resulted in a possibly harmful change of performance in Ice2 protocol (-0.5 ± 8.9%) compared to Ice1 protocol (-1.0 ± 5.1%). On-ice training is more effective in the development of specific types of agility in adolescent U16 players. However, there is evidence that off-ice agility have motor transfer to on-ice agility. Therefore, we recommend developing on-ice agility with additional off-ice agility training during the ice hockey season.