The Influence of Maturity Status on Dynamic Balance Following 6 Weeks of Eccentric Hamstring Training in Youth Male Handball Players

Information about when to apply an appropriate eccentric hamstring strength training stimulus during long-term athlete development is essential for effective programming and improving balance performance. This study examined the effects of six-week eccentric hamstring training on dynamic balance performance in youth handball players of different maturity statuses (pre- or post-peak height velocity (PHV)). A randomized controlled design with 45 young male handball players (14.6 ± 0.3 years) from a local national handball club were randomly allocated to a 6 week, twice weekly eccentric hamstring training in two experimental groups: a pre-PHV (maturation offset: −2.13 ± 0.63, n = 10) and post-PHV (maturation offset: 0.79 ± 0.34, n = 12) group and two control groups: maturation offset: −2.09 ± 0.61, n = 10 and maturation offset: 0.55 ± 0.67, n = 13. Dynamic balance performance was evaluated by using the composite score during the lower quarter Y-balance test from pre- and post-intervention. A significant effect on balance scores was found from pre to post (F = 11.4; p = 0.002; η(2)(p) = 0.22), intervention (F = 5.4; p = 0.025; η(2)(p) = 0.12), and maturation (F = 369; p < 0.001; η(2)(p) = 0.9), but no significant interaction effects were found (F ≥ 3.3; p ≥ 0.077; η(2)(p) ≤ 0.07). Post hoc analysis revealed that the post-PHV group had a higher score than the pre-PHV group. Furthermore, that dynamic balance increased in the post-PHV group after intervention much more in the control post-PHV group. It was concluded that somatic maturation influences dynamic balance performance and that eccentric hamstring training results in greater improvement in balance performance in young male handball players for the post-pubertal group

The Effects of Eccentric and Plyometric Training Programs and Their Combination on Stability and the Functional Performance in the Post-ACL-Surgical Rehabilitation Period of Elite Female Athletes

BackgroundThe standard method to treat physically active patients with anterior cruciate ligament (ACL) rupture is ligament reconstruction surgery. The rehabilitation training program is very important to improve functional performance in recreational athletes following ACL reconstruction.ObjectivesThe aims of this study were to compare the effects of three different training programs, eccentric training (ECC), plyometric training (PLYO), or combined eccentric and plyometric training (COMB), on dynamic balance (Y-BAL), the Lysholm Knee Scale (LKS), the return to sport index (RSI), and the leg symmetry index (LSI) for the single leg hop test for distance in elite female athletes after ACL surgery.Materials and MethodsFourteen weeks after rehabilitation from surgery, 40 elite female athletes (20.3 ± 3.2 years), who had undergone an ACL reconstruction, participated in a short-term (6 weeks; two times a week) training study. All participants received the same rehabilitation protocol prior to the training study. Athletes were randomly assigned to three experimental groups, ECC (n = 10), PLYO (n = 10), and COMB (n = 10), and to a control group (CON: n = 10). Testing was conducted before and after the 6-week training programs and included the Y-BAL, LKS, and RSI. LSI was assessed after the 6-week training programs only.ResultsAdherence rate was 100% across all groups and no training or test-related injuries were reported. No significant between-group baseline differences (pre-6-week training) were observed for any of the parameters. Significant group-by-time interactions were found for Y-BAL (p &lt; 0.001, ES = 1.73), LKS (p &lt; 0.001, ES = 0.76), and RSI (p &lt; 0.001, ES = 1.39). Contrast analysis demonstrated that COMB yielded significantly greater improvements in Y-BAL, LKS, and RSI (all p &lt; 0.001), in addition to significantly better performances in LSI (all p &lt; 0.001), than CON, PLYO, and ECC, respectively.ConclusionIn conclusion, combined (eccentric/plyometric) training seems to represent the most effective training method as it exerts positive effects on both stability and functional performance in the post-ACL-surgical rehabilitation period of elite female athletes

The effects of Nordic hamstring exercise on pain and performance in elite rowers with low back pain

The aim of the present study was to examine the effects of the Nordic hamstring exercise (NHE) on pain threshold, flexibility and 2000m rowing performance in elite rowers with lower back pain (LBP). Ten elite rowers (age 17.6 ± 2.12 years) with LBP participated in this study. Participants completed 6-weeks of NHE in addition to their usual training program. Pre- and post-training tests included measures of pain threshold of the lower back, flexibility (sit and reach test) and 2000 m rowing performance. The results demonstrated that an organized HNE caused a significant decrease in pain threshold from 4.8±2 to 3±1.4 (P = 0.03, ES = 0.9) and a non-significant but moderate improvement in rowing performance from 6.9±0.7 min to 6.3±0.9 min (P = 0.1, ES = 0.8). The sit and reach test revealed a non-significant change from 14.9±8.2 cm to 15.2±6.5 cm (P = 0.9, ES = 0.04). We conclude that the NHE may represent an effective method for reducing pain in elite rowers with moderate improvement in rowing performance

The effects of Nordic hamstring exercise on pain and performance in elite rowers with low back pain

The aim of the present study was to examine the effects of the Nordic hamstring exercise (NHE) on pain threshold, flexibility and 2000m rowing performance in elite rowers with lower back pain (LBP). Ten elite rowers (age 17.6 ± 2.12 years) with LBP participated in this study. Participants completed 6-weeks of NHE in addition to their usual training program. Pre- and post-training tests included measures of pain threshold of the lower back, flexibility (sit and reach test) and 2000 m rowing performance. The results demonstrated that an organized HNE caused a significant decrease in pain threshold from 4.8±2 to 3±1.4 (P = 0.03, ES = 0.9) and a non-significant but moderate improvement in rowing performance from 6.9±0.7 min to 6.3±0.9 min (P = 0.1, ES = 0.8). The sit and reach test revealed a non-significant change from 14.9±8.2 cm to 15.2±6.5 cm (P = 0.9, ES = 0.04). We conclude that the NHE may represent an effective method for reducing pain in elite rowers with moderate improvement in rowing performance

Blood pressure, heart rate and perceived enjoyment after small-sided soccer games and repeated sprint in untrained healthy adolescents

The purpose of this study was to examine systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR), rating of perceived exertion (RPE) and perceived enjoyment responses to a repeated-sprint training session (RST) compared to a small-sided soccer game session (SSG) in untrained adolescents. Twelve healthy post-pubertal adolescent males (age 15.8±0.6 years, body mass 59.1±3.7 kg, height 1.7±0.1m) performed RST and SSG sessions in a randomized and counterbalanced order. Blood pressure and HR were measured at rest and at 10, 20 and 30 minutes after interventions, and RPE and enjoyment were assessed. RST and SSG elicited similar exercise HR (74.0% vs. 73.7% of HR peak during RST and SSG respectively, P>0.05). There was no significant change in SBP or DBP after the 2 interventions (all P>0.05, ES<0.5) with a trend to a decrease in SBP after SSG at 30 min after intervention (moderate effect, ES=0.6). Pearson’s correlation analysis revealed a significant and large correlation between baseline BP values and magnitude of decline after both RST and SSG. Heart rate during recovery was higher compared with baseline at all times after both sessions (all P<0.05), with HR values significantly lower after SSG versus RST at 30 min after interventions (82.3±3.2 versus 92.4±3.2 beats/min, respectively, P=0.04). RPE was significantly lower (P=0.02, ES=1.1) after SSG than after RST, without significant differences in enjoyment. In conclusion, repeated sprint and small-sided games elicited similar exercise intensity without a significant difference in perceived enjoyment. Post-exercise hypotension after the two forms of training may depend on resting BP of subjects

It Is Time to Play: Acute Effects of Soccer and Sprint Exercise on Attentional Performance, Mood, and Enjoyment in Untrained Male Adolescents

This study aimed to compare the effects of an acute bout of small-sided soccer game (SSG) and sprint exercise on attention, mood, and enjoyment in untrained adolescent boys. Eighteen adolescent boys aged 13–15 years participated in a counterbalanced order intervention: 1—No-training control condition (CONTROL), 2—SSG (SOCCER), and 3—Repeated sprint (SPRINT) sessions. Before and after the sessions, all participants completed the revised d2-test of attention and a mood assessment (i.e., Brunel mood scale [BRUMS]). Rating of perceived exertion (RPE) and perceived enjoyment (i.e., physical activity enjoyment scale) were evaluated after each session. A 3 × 2 repeated measures analysis of variance with contrast-coded test was used to analyze the data. Attentional test performance increased from pre- to post-exercise intervention for both SOCCER and SPRINT (main effect of Phase, F = 40.81, p < .001, ηp 2 = 0.48), compared with the CONTROL. BRUMS scores did not change for any of the interventions. RPE was significantly lower after SOCCER compared with SPRINT ( t = 3.05 [3.20–7.18], p < .001, ηp 2 = 0.46). SOCCER was perceived to be significantly more enjoyable compared with SPRINT ( p = .03) and CONTROL ( p < .001). To conclude, an acute bout of exercise based on SOCCER or SPRINT exercise was beneficial for adolescent boys’ attention, with significantly better enjoyment reported after the SOCCER session, whereas we did not observe any mood effects

Evidence of nonlocal muscle fatigue in male youth

Evidence for nonlocal muscle fatigue (NLMF) has been inconsistent in adults, with no studies investigating youth. The objective was to examine NLMF in youth. Forty-two young males (age, 10–13 years) were tested for maximal voluntary isometric contraction (MVIC) force of the ipsilateral and contralateral knee extensors at 90° and 120° knee flexion, elbow flexors at 90°, handgrip, knee extensor isokinetic torque (300°·s −1 analyzed at 90° and 120° knee flexion), as well as a unilateral countermovement jump (CMJ) and Y Balance test (YBT). Isokinetic fatigue group (n = 15) had unilateral fatigue induced with 10 sets of 20 repetitions of maximal isokinetic knee extensor contractions at 300°·s −1 . Isometric fatigue group (n = 15) used 10 repetitions of 6-s knee extensor MVIC whereas the control group (n = 12) were not fatigued. There was no significant difference in the response to the isometric- or isokinetic-fatigue intervention protocols. Main time effects indicated that NLMF was evident with the contralateral knee extensor MVIC at 90° (p = 0.008; 8.9%), knee extensor isokinetic torque at 90° (p < 0.001; 11.4%), and 120° (p = 0.05; 5.4%), CMJ (p = 0.02; 11.5%), handgrip (p = 0.06; 4.5%), elbow flexors (p < 0.001; 7.7%), and YBT (p = 0.001; 5.6%). Ipsilateral NLMF deficits occurred with handgrip (p < 0.001; 7.3%), elbow flexors MVICs (p < 0.001; 10.7%), CMJ (p = 0.02; 12.2%), and YBT (p = 0.002; 3.8%). NLMF with similar relative fatigue-induced deficits of fatigued and nonfatigued limbs suggest that youth fatigue is highly dependent upon the extent of activation or inhibition of the nervous system. Coaches of young athletes might consider developing technical motor skills before fatiguing exercise components, which might hinder the proficiency of their performance

Unilateral static and dynamic hamstrings stretching increases contralateral hip flexion range of motion

Static (SS) and dynamic stretching (DS) can lead to subsequent performance impairments or enhancement with the stretched limb. Crossover or non-local muscle fatigue (NLMF) refers to unilateral fatigue-induced impairments in a contralateral or non-exercised muscle. Whereas there are conflicting findings in the NLMF literature, there are few studies examining the effect of an acute bout of SS or DS on contralateral flexibility, torque or power. Fourteen highly trained subjects (means ± standard deviations: 18 ± 2 years; 179·4 ± 4·6 cm; 70·5 ± 6·3 kg; %body fat: 10·7 ± 2·5%) were tested before and following separate sessions of eight repetitions of 30 s of unilateral hip flexion SS or DS. Pre- and postintervention testing at 1 and 10 min included hip flexor range of motion (ROM), isokinetic leg flexion torque and power at 60°.s(-1) and 300°.s(-1) of the stretched and contralateral limbs. The stretched limb had a 6·3% (P = 0·01; ES: 0·91) ROM increase with DS at 10 min. The contralateral non-stretched hip flexors experienced ROM increases with SS of 5·7% (P = 0·02; ES: 0·68) from pretest to 1 min post-test, whereas DS showed 7·1% (P<0·0001; ES: 1·09) and 8·4% (P = 0·005; ES: 0·89) increases, respectively. There were no relative differences in ROM changes between conditions or limbs nor any stretch-induced changes in isokinetic torque or power. In conclusion, unilateral SS and DS augment contralateral limb ROM likely through an increased stretch tolerance

Effects of soccer training on health-related physical fitness measures in male adolescents

Purpose: The aims of this study were to (1) investigate the health-related physical fitness profile of untrained adolescent boys in comparison to adolescent soccer players, (2) determine the intensity and enjoyment of 6 v 6 and 4 v 4 small-sided games, and (3) evaluate the health-related effects of a short-period of soccer training in the untrained group. Methods: Forty-one adolescent boys (untrained, n = 24: age = 15.9 ± 0.6 years; trained, n = 17: age = 15.7 ± 0.7 years) were recruited. For Purpose 1, the players (n = 17) and the untrained (n = 24) boys were tested for speed, jumping power, postural balance, flexibility, and aerobic capacity. After baseline testing, Purposes 2 and 3 were addressed by randomly assigning the untrained boys to either a soccer-training group (small-sided games, 2 sessions per week for 8 weeks) or to a control group, followed by identical retesting. Results: At baseline, physical fitness was higher (p < 0.001) in trained players than in untrained for aerobic fitness, sprinting, jumping power, and postural balance. Small-sided games using 6 v 6 or 4 v 4 elicited similar heart rate (HR) (mean:  ~ 85% peak heart rate, HRpeak), rate of perceived exertion, and enjoyment responses. Over 8 weeks, the between-group analysis revealed that soccer training had a large beneficial effect on postural balance (45%) when compared with control group with unclear effects on other fitness parameters. Conclusion: Adolescent soccer players had markedly higher physical fitness compared with untrained adolescents. Small-sided soccer games practiced by untrained adolescents elicited high exercise intensity. While 8 weeks of twice-weekly soccer training sessions induced significant improvement in postural balance, the short duration of the study was not sufficient to result in between-group differences in sprint and jump performance or aerobic fitness. Keywords: Enjoyment, Football, Heart rate, Small-sided games, Trainin

D oes the moon cycle affect the physical endurance, balance, reaction-time, mood state and well-being in trained athletes?

BACKGROUND: Fascination with the moon has spanned millennia. It has recently been asserted that the moon cycle affects endurance performance in untrained individuals. The present study aimed at investigating the effects of the lunar cycle on intermittent endurance physical performance, balance and reaction-time capabilities, and selected physiological and psychological parameters in trained athletes. METHODS: Twelve male Taekwondo athletes (age, 22.3±0.8 years; height, 178.8±6.5 cm; body mass, 72.75±7.28 kg; %body fat, 13.9±3.6%) performed the Yo-Yo intermittent recovery test level-1 (YYIRT), the Y-balance test (YBT), and a reaction-time test (RT) during different lunar cycle phases (new moon (NM), full moon (FM), and half-moon). Participants' psychological profiles and well-being indices (i.e. a profile of mood state (POMS) and Hooper Index) were also taken during each moon phase. The testing sessions during the different moon phases were performed in a counterbalanced order. The tests order remained the same (POMS, then Hooper index, RT, YBT, YYIRT and rating of perceived exertion scale (RPE)), and all sessions were performed at noon (11:00 to 13:00 h) during the first day of each evaluated lunar phase. RESULTS: Analysis of variance tests showed that no significant differences were found between the three moon phases in all analyzed variables. CONCLUSIONS: This study showed that the different lunar cycle phases did not have significant effects on the selected physical performances and psychological indices in trained athletes. © 2019 EDIZIONI MINERVA MEDICA.Scopu