Anthropometric characteristics of young elite sailors based on performance level.

Background: /Objectives: The aim of the present study was to analyse possible differences in anthropometric characteristics of elite sailors based on categories and performance level. Methods: ː A total of 42 young (aged 12-18 years) elite sailors (men = 31; women = 11) of the Monohull (n = 21) and Windsurfing (n = 21) categories composed the study sample. Testing was per-formed in one session the day before the start of an official and international competition. Body composition was measured using an octopolar and multi-frequency electrical bioimpedance analyser, and height was recorded using a telescopic measuring instrument. Cross-sectional study. The total sample was divided into two groups based on their performance level (ranking), 50th percentile (P1), and 100th percentile (P2). Results: ː P1 presented a lower BMI, total body fat mass, and body fat mass in the trunk, arms, and legs (p < 0.05). Similarly, P1 reported a higher total body muscle mass and body muscle mass on the trunk, arms, and legs compared to the less level performance group (p < 0.05). In addition, P2 sailors were taller and heavier (p < 0.05). Regarding categories, the Windsurf sailors presented statistically significantly lower arm fat mass than the Monohull (p < 0.05). The Windsurf sailors showed differences between the two performance-level groups (p < 0.05). Additionally, comparing the high-level performance group in both categories, higher arm muscle mass on the Windsurfing sailors was detected (p < 0.05). Conclusions: ː These findings could help to differentiate the anthropometric variables that determine sport performance in young elite sailors and could be used to differentiate the anthropometric variables in each category.

The Acute Effects of Normobaric Hypoxia on Strength, Muscular Endurance and Cognitive Function: Influence of Dose and Sex.

The aim of this study was to examine the acute effects of different levels of hypoxia on maximal strength, muscular endurance, and cognitive function in males and females. In total, 13 males (mean ± SD: age, 23.6 ± 2.8 years; height, 176.6 ± 3.9 cm; body mass, 76.6 ± 2.1 kg) and 13 females (mean ± SD: age, 22.8 ± 1.4 years; height, 166.4 ± 1.9 cm; body mass, 61.6 ± 3.4 kg) volunteered for a randomized, double-blind, crossover study. Participants completed a one repetition strength and muscular endurance test (60% of one repetition maximum to failure) for squat and bench press following four conditions; (i) normoxia (900 m altitude; FiO2: 21%); (ii) low dose hypoxia (2000 m altitude; FiO2: 16%); (iii) moderate dose hypoxia (3000 m altitude; FiO2: 14%); and (iv) high dose hypoxia (4000 m altitude; FiO2: 12%). Heart rate, blood lactate, rating of perceived exertion, and cognitive function was also determined during each condition. The one repetition maximum squat (p = 0.33) and bench press (p = 0.68) did not differ between conditions or sexes. Furthermore, squat endurance did not differ between conditions (p = 0.34). There was a significant decrease in bench press endurance following moderate (p = 0.02; p = 0.04) and high (p = 0.01; p = 0.01) doses of hypoxia in both males and females compared to normoxia and low dose hypoxia, respectively. Cognitive function, ratings of perceived exertion, and lactate were also significantly different in high and moderate dose hypoxia conditions compared to normoxia (p < 0.05). Heart rate was not different between the conditions (p = 0.30). In conclusion, high and moderate doses of acute normobaric hypoxia decrease upper body muscular endurance and cognitive performance regardless of sex; however, lower body muscular endurance and maximal strength are not altered.

Effects of ß-Hydroxy ß-Methylbutyric Supplementation in Combination with Conservative Non-Invasive Treatments in Athletes with Patellar Tendinopathy: A Pilot Study.

The aim of the present study was to analyze the effect of conservative non-invasive treatments based on eccentric training, stretching and extracorporeal shock wave therapy (ESWT) supplemented with ß-Hydroxy ß-methylbutyric (HMB) or placebo (PLAC) on body composition, pain and muscular function (jump ability, muscular power and muscular strength) in athletes with patellar tendinopathy (PT). In a double-blind randomized trial, 8 athletes (4 males and 4 females) performed a physical rehabilitation for 4 weeks. They were randomly divided into two experimental groups (two males and two females in each one) that ingested HMB (HMBG) or PLAC (PLACG). In pre- and post-intervention were assessed body composition, pain, countermovement jump (CMJ), back-squat (BS) for analyzing peak power (W) (PPPP), load (kg) associated to PPPP (PPKG) and mean velocity (m/s) (PPMV) in addition to a 5-RM leg extension tests. An interaction intervention·supplementation (p = 0.049; È 2p = 0.774) was observed in the height reached in the CMJ as an intervention effect in PPPP detected for the HMBG (p = 0.049). In addition, an enhancement in PPKG (p = 0.028; È 2p = 0.842) was detected in the intervention, but not in PPMV, as an increase in the intervention in the 5-RM test (p = 0.001; È 2p = 0.981) was observed. No changes were noted on body composition or pain (p > 0.05). The combination of eccentric training with stretching and ESWT increased concentric muscular power and strength after 4 weeks without changes in body lean mass or pain. In addition, HMB supplementation could enhance the power muscular performance in athletes with PT, optimizing the intervention adaptions.

High Dose of Caffeine Mouth Rinse Increases Resistance Training Performance in Men.

Caffeine mouth rinsing (CMR) has been shown to enhance exercise performance. However, no studies have analyzed the effects of different dosages of CMR on muscular performance. Therefore, the purpose of this study was to examine the effects of different dosages of CMR on strength (bench press 1 repetition maximum (1-RM)) and muscular endurance (60% of 1-RM repetitions to failure) in resistance-trained males. Fourteen resistance-trained males (age: 23 ± 2 years, height: 179 ± 3 cm, body mass: 83 ± 4 kg, BMI: 17 ± 2 kg/m2) completed four conditions in random order. The four conditions consisted of a mouth rinse with 25 mL solutions containing either 1% (250 mg) of CMR (low dose of CMR: LCMR), 2% (500 mg) of CMR (moderate dose of CMR: MCMR), 3% (750 mg) of CMR (high dose of CMR: HCMR) and sweetened water (placebo: PLA) for 5 s prior to a bench press strength and muscular endurance test. Maximal strength, muscular endurance, heart rate (HR) and ratings of perceived exertion (RPE) were recorded for each condition. There were no significant differences in strength (p = 0.30) and HR (p = 0.83) between conditions. HCMR significantly increased muscular endurance performance (p = 0.01) and decreased RPE values (p = 0.01). In conclusion, CMR did not affect bench press 1-RM strength performance, but muscular endurance responses to CMR seems to be dose-dependent.

Loss of kinesin-8 improves the robustness of the self-assembled spindle in Schizosaccharomyces pombe.

Chromosome segregation in female meiosis in many metazoans is mediated by acentrosomal spindles, the existence of which implies that microtubule spindles self-assemble without the participation of the centrosomes. Although it is thought that acentrosomal meiosis is not conserved in fungi, we recently reported the formation of self-assembled microtubule arrays, which were able to segregate chromosomes, in fission yeast mutants, in which the contribution of the spindle pole body (SPB; the centrosome equivalent in yeast) was specifically blocked during meiosis. Here, we demonstrate that this unexpected microtubule formation represents a bona fide type of acentrosomal spindle. Moreover, a comparative analysis of these self-assembled spindles and the canonical SPB-dependent spindle reveals similarities and differences; for example, both spindles have a similar polarity, but the location of the γ-tubulin complex differs. We also show that the robustness of self-assembled spindles can be reinforced by eliminating kinesin-8 family members, whereas kinesin-8 mutants have an adverse impact on SPB-dependent spindles. Hence, we consider that reinforced self-assembled spindles in yeast will help to clarify the molecular mechanisms behind acentrosomal meiosis, a crucial step towards better understanding gametogenesis.

Analysis of the consumption of sports supplements in elite fencers according to sex and competitive level.

BACKGROUND: The aim of this study was to analyze the consumption of sports supplements (SS) in competitive level fencers and compare differences based on sex and competitive level (international and national). METHODS: A total of 49 fencers (18 men and 31 women) of national (n = 16) and international (n = 33) level completed a questionnaire with questions about SS consumption and the possible repercussions on health and / or sports performance. The results were analyzed based on the different categorizations established by the Australian Institute of Sport (AIS), as well as by sex and level of competence to which the participants belonged to. RESULTS: 46.9% of fencers have consumed SS with the main motivation being performance improvement (34.2%). Medical doctors were the individuals who were more likely to advise men to consume SS (50.0% vs 5.6%; OR = 3.29 [1.50-7.20]). Friends were most likely to advise women (38.9% vs 8.3%; OR = 1.75 [1.05-2.93]). The most consumed SS were sport drinks (44.9%), vitamin C (43.4%), sport bars (38.8%), and caffeine (28.6%). In regards to the SS categories, it was observed differences in the interaction level·sex in medical supplements (p = 0.017). In addition, there was a higher prevalence of whey protein consumption in women (25.8% vs 0%; p = 0.020) and iron consumption in men (33% vs 6.5%; p = 0.039). CONCLUSIONS: The prevalence of SS use in fencers is within the values previously reported in athletes of the same competitive level. There were no differences by sex and competitive level in the total consumption of SS, nor in each of the groups of level of evidence, being sport drinks, bars and caffeine the most consumed SS.

Efficacy of two different stretch training programs (passive vs. proprioceptive neuromuscular facilitation) on shoulder and hip range of motion in older people.

The aim of this study was to determine the influence of 2 methods of stretch training (passive and proprioceptive neuromuscular facilitation [PNF]) on range of motion (ROM) in older people between the age of 60 and 70 years over a period of 13 weeks. Fifty-four participants (39 women and 15 men) were divided into 3 groups: passive (n = 17; 66.5 ± 6.5 years), PNF (n = 17; age, 64.7 ± 4.0 years old), and control (n = 17; age, 66.4 ± 4.5 years). The subjects trained 2 times per week on nonconsecutive days for 13 weeks. Each training session included 2 flexibility exercises focused on the shoulder and hip joints. The PNF group performed 6 seconds of passive stretching, 3 seconds of muscular contractions, and 2 seconds of relaxation. The passive group performed 10 seconds of stretching and 5 seconds of relaxation. This sequence was repeated 3 times by each group. The control group did not perform any stretching. In the PNF group, there was an increase in hip ROM (p < 0.001) between pretest and posttest in the passive group and an improvement (p < 0.001) was observed between pretest and posttest, whereas in the control group, there was a significant decrease (p < 0.01) in hip ROM between pretest and posttest. In shoulder ROM, there was an increase (p < 0.001) between pretest and posttest in the passive group and an improvement (p < 0.001) was observed between pretest and posttest in the PNF group. There were no changes in shoulder ROM between pretest and posttest in the control group. The analysis of variance showed significant differences in hip and shoulder ROM between passive and control groups and PNF and control groups, but no significant differences were found between passive and PNF. The main finding was that the ability of physically active older people to increase ROM in response to stretching techniques is similar for both passive and PNF techniques.