50 research outputs found

    Assessment of Autonomic Cardiac Activity in Athletes

    Get PDF
    Athletes, coaches, and supporting staff should assume a scientific approach to both designing and monitoring training programs. Proper load monitoring is essential to determine whether an athlete is adapting to a training program and to minimize the risk of increasing non-functional overreaching, illness, or injury. To gain an understanding of training and competition demands and their effects on the athlete, various potential physiological variables are available. Nonetheless, very few of them have robust scientific evidence to support their use. Therefore, this chapter will discuss the use of non-invasive and time-efficient methods to record and/or calculate heart rate variability (HRV) in athletes. HRV variables can provide detailed information about positive and negative adaptions over short and long periods throughout the competitive season. The accumulated knowledge regarding the importance of HRV has led both monitoring variables to become popular strategies among elite athletes, coaches, and supporting staff

    The Importance of Sleep in Athletes

    Get PDF
    Sleep is an essential component for athletes’ recovery from fatigue, due especially to its physiological and psychological restorative effects. Moreover, sleep is extremely important for numerous biological functions, and sleep deprivation can have significant effects on athletic performance in short-, medium-, and long term. For example, and considering the physiology of sleep for athletes, some hormonal responses that take place in the lead up to and during sleep (e.g., growth hormone—important role in muscle growth and repair) may be affected following exercise (i.e., training and competition), especially when compared with non-athlete’s populations. Thus, monitoring sleep is also crucial to understand responses to training and readiness, enabling appropriate planning. Importantly, sleep monitoring also intends to reduce the risk of injury, illness, and nonfunctional overreaching. Moreover, an “individual approach” in athletes monitoring could help in better prescribe training contents and more adequately manage fatigue, as well as recommend pertinent post-match recovery strategies, such as sleep hygiene interventions. Overall, for understanding the athlete’s sleep patterns/responses and to optimize the recovery strategies, it is crucial for comprehensive monitoring of his/her health, performance, fitness, and fatigue status

    Reliability of heart rate variability in futsal players

    Get PDF
    The main aim the present study was evaluated the reliability of the heart rate variability (HRV) indices in futsal players. Additionally the study verifi ed the reliability of different approaches for 5 min interval selection of recording. Eighteen under-20 futsal players underwent 15 min of pre-training RR interval recordings in two different day. Time and frequency domain and Poincaré Plot indices were tested. The indices were calculated using: 1) fi nal 5 min of recording; 2) 5 min of lower variance of recording, by a mathematical algorithm; 3) 5 min segment of lower variance, by an experienced operator. The HRV indices presented a wide range reliability [e.g. RRmean (ICC=0.96, SEM=3.4ms, CV=2.6%), lnRMSSD (ICC=0.88, SEM=5.9ms, CV=4.3%), lnHF (ICC=0.89, SEM=7.5ms, CV=5.9%), LFnu (ICC=0.84, SEM=13ms, CV=9.4%), LF (ICC=0.47, SEM=65.2ms,CV=38.5%) and LF/HF (ICC=0.63, SEM=83.7ms, CV=54.5%)]. The fi nal 5 min of recording was the most reliable. The results suggest that most of HRV indices presented acceptable reliability, however the RRmean, lnRMSSD, lnHF and LFnu were the most reliable

    Report on the first Combat Sports Special Interest Group meeting at the 28th Annual Congress of the European College of Sport Science, and call for action

    Get PDF
    This short report describes the process of creating the Combat Sports Special Interest Group (CSSIG), its first meeting at the 28th Annual Congress of the European College of Sport Science (ECSS, Paris 4-7 July, 2023), and to make a call for action for the next events. The first contact between the group that proposed the creation of the CSSIG was made after a session of the Annual Congress of the ECSS held in 2022, but the idea and format of the proposal was initiated in January 2023. After its approval the CSSIG set the topics for the first meeting. During the 2023 edition the ECSS event had eight special interest groups, including the CSSIG. The first meeting of the CSSIG included the presentation of its goals, and two short presentations: one related to combat sports athletes’ health, and the other on testing and training monitoring of judo athletes. The aim of the CSSIG is to establish a sustainable network fostering evidence-based research and practice of combat sports, in order to: (a) promote health and safety of combat sports participants, (b) enhance their performance, and (c) improve training and competition practices. Thus, this report is also a call for action for the next events

    Monitoring training load in beach volleyball players: a case study with an Olympic team

    Get PDF
    Abstract AIM Describe and compare training load dynamics of two Olympic beach volleyball players. METHODS Two Olympic beach volleyball players participated in this study (specialist defender and blocker: both aged 34 years, holding 14 years of competitive experience, height: 1.74 m and 1.81 m, weight: 69 kg and 65 kg, respectively). Internal training load (ITL), total weekly training load (TWTL), monotony and strain were obtained through the session rating of perceived exertion (session-RPE) for three training mesocycles (10 weeks). Lower limb explosive power was assessed through the counter movement jump (CMJ). RESULTS Mean ITL, TWTL, monotony and strain during the 10-week period were: 370 ± 156; 1997 ± 838; 2.7 ± 1.3; 5621 ± 1802 arbitrary units (AU) (Defender) and 414 ± 153; 2392 ± 892; 2.7 ± 1.1; 6894 ± 3747 (AU) (Blocker). Mean of CMJ height was 47.0 ± 1.3 and 40.3 ± 1.6 cm, for the defender and blocker, respectively. The defender player presented higher ITL in the second (effect size (ES) = 0.90; 92/5/3, likely) and in the third (ES = 0.91; 94/4/2, likely) mesocycles when compared to the first. Monotony raised from the first to the third mesocycle (ES = 2.91; 98/1/1, very likely). Blocker's ITL was higher in the third mesocycle than the first (ES = 1.42. 98/1/1, very likely) and the second (ES = 1.49; 98/1/1, likely) ones. CONCLUSION ITL magnitude increased from the first to the third mesocycle, in both players

    Effects of high-intensity training with one versus three changes of direction on youth female basketball players’ performance

    Get PDF
    To compare the effects of high-intensity interval training (HIT) with one versus three changes of direction (COD) on young (age, 17.2±1.1 years) female basketball players’ performance, six weeks of regular basketball training (control period) was followed by six weeks of high-intensity training added to regular training , two times per week, with a random allocation of athletes to either HIT with one (HIT-COD1; n=6) or three COD (HIT-COD3; n=6). Before and after the control and HIT-COD training periods athletes performed repeatedsprint ability test (RSA), modified agility T-test (MAT), V-cut, triple standing dominant (TS-D) and nondominant (TS-ND) jump, TS-D and TS-ND with COD tests, and 30-15 Intermittent Fitness Test (30-15IFT). With the exception of a substantial improvement in V-cut in both groups, no substantial changes occurred during the control period. Both HIT-COD training programs improved V-cut, although only HIT-COD3 substantially improved RSA mean time (RSAm), MAT and the final speed reached in 30-15IFT (VIFT). The between-group comparison revealed greater improvements in RSAm and VIFT in HIT-COD3 than in HITCOD1. In conclusion, supplementation of basketball training with HIT-COD drills adds improvements to young female basketball player’s performance, especially when 3 COD are incorporated into HIT

    Squat and countermovement jump performance across a range of loads: A comparison between Smith machine and free weight execution modes in elite sprinters

    Get PDF
    The aims of this study were to: 1) provide and compare the height achieved during Smith machine (SM) and free weight (FW) loaded jumps executed over a wide spectrum of loads (40–120 % of body mass [BM]); and 2) test the difference between loaded and unloaded squat jump (SJ) and countermovement jump (CMJ) attempts in ten highly trained male sprinters. On the first visit, athletes performed unloaded SJ and CMJ, loaded SJ with loads corresponding to 40, 60, 80, 100, and 120 % BM, and loaded CMJ at 100% BM using an Olympic barbell (FW). On the second visit, they performed loaded SJ and CMJ tests under the same loading conditions on the SM device and, subsequently, a half-squat one-repetition maximum (1RM) assessment. The relative strength (RS = 1RM/BM) of the athletes was 2.54 ± 0.15. Loaded SJ performance was similar between SM and FW, and across all loading conditions. Differences in favour of CMJ (higher jump heights compared with SJ) were superior in the unloaded condition but decreased progressively as a function of loading. In summary, sprinters achieved similar SJ heights across a comprehensive range of loads, regardless of the execution mode (FW or SM). The positive effect of the countermovement on jump performance is progressively reduced with increasing load

    Effects of Plyometric Training and Beta-Alanine Supplementation on Maximal-Intensity Exercise and Endurance in Female Soccer Players.

    Get PDF
    Plyometric training and beta-alanine supplementation are common among soccer players, although its combined use had never been tested. Therefore, a randomized, double-blind, placebo-controlled trial was conducted to compare the effects of a plyometric training program, with or without beta-alanine supplementation, on maximal-intensity and endurance performance in female soccer players during an in-season training period. Athletes (23.7 ± 2.4 years) were assigned to either a plyometric training group receiving a placebo (PLACEBO, n = 8), a plyometric training group receiving beta-alanine supplementation (BA, n = 8), or a control group receiving placebo without following a plyometric training program (CONTROL, n = 9). Athletes were evaluated for single and repeated jumps and sprints, endurance, and change-of-direction speed performance before and after the intervention. Both plyometric training groups improved in explosive jumping (ES = 0.27 to 1.0), sprinting (ES = 0.31 to 0.78), repeated sprinting (ES = 0.39 to 0.91), 60 s repeated jumping (ES = 0.32 to 0.45), endurance (ES = 0.35 to 0.37), and change-of-direction speed performance (ES = 0.36 to 0.58), whereas no significant changes were observed for the CONTROL group. Nevertheless, compared to the CONTROL group, only the BA group showed greater improvements in endurance, repeated sprinting and repeated jumping performances. It was concluded that beta-alanine supplementation during plyometric training may add further adaptive changes related to endurance, repeated sprinting and jumping ability

    Reprogramming energy metabolism and inducing angiogenesis : co-expression of monocarboxylate transporters with VEGF family members in cervical adenocarcinomas

    Get PDF
    Background: Deregulation of cellular energetic metabolism was recently pointed out as a hallmark of cancer cells. This deregulation involves a metabolic reprogramming that leads to a high production of lactate. Lactate efflux, besides contributing for the glycolytic flux, also acts in the extracellular matrix, contributing for cancer malignancy, by, among other effects, induction of angiogenesis. However, studies on the interplay between cancer metabolism and angiogenesis are scarce. Therefore, the aim of the present study was to evaluate the metabolic and vascular molecular profiles of cervical adenocarcinomas, their co-expression, and their relation to the clinical and pathological behavior. Methods: The immunohistochemical expression of metabolism-related proteins (MCT1, MCT4, CD147, GLUT1 and CAIX) as well as VEGF family members (VEGF-A, VEGF-C, VEGF-D, VEGFR-1, VEGFR-2 and VEGFR-3) was assessed in a series of 232 cervical adenocarcinomas. The co-expression among proteins was assessed and the expression profiles were associated with patients’ clinicopathological parameters. Results: Among the metabolism-related proteins, MCT4 and CAIX were the most frequently expressed in cervical adenocarcinomas while CD147 was the less frequently expressed protein. Overall, VEGF family members showed a strong and extended expression with VEGF-C and VEGFR-2 as the most frequently expressed and VEGFR-1 as the less expressed member. Co-expression of MCT isoforms with VEGF family members was demonstrated. Finally, MCT4 was associated with parametrial invasion and HPV18 infection, CD147 and GLUT1 with distant metastasis, CAIX with tumor size and HPV18 infection, and VEGFR-1 with local and lymphnode metastasis. Conclusions: The results herein presented provide additional evidence for a crosstalk between deregulating cellular energetics and inducing angiogenesis. Also, the metabolic remodeling and angiogenic switch are relevant to cancer progression and aggressiveness in adenocarcinomas.CP received a post-doctoral fellowship (SFRH/BPD/69479/2010) and FM-S received a doctoral fellowship (SFRH/BD/87139/2012) from FCT (Portuguese Foundation for Science and Technology). This work was supported by the FCT grant ref. PTDC/SAU-FCF/104347/2008, under the scope of "Programa Operacional Tematico Factores de Competitividade" (COMPETE) of "Quadro Comunitario de Apoio III" and co-financed by Fundo Comunitario Europeu FEDER, and also by FAPESP 2008/03232-1
    corecore