فهرست مطالب

Sports Medicine - Volume:9 Issue: 2, Jun 2018

Asian Journal of Sports Medicine
Volume:9 Issue: 2, Jun 2018

  • تاریخ انتشار: 1397/04/11
  • تعداد عناوین: 9
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  • Maria Fernandez-Del-Valle *, Matthew J. Short, Eunhee Chung, Jacalyn Mccomb, Shelby Kloiber, Fernando Naclerio, Eneko Larumbe-Zabala Page 1
    Background
    Existing research suggests that irisin increases in response to exercise in humans. However, results are controversial and a majority of the studies lack a control group. The present study aimed to analyze the effects of both one-bout, and three-week intense resistance training on physical fitness (body composition and strength) and serum irisin levels when compared to a control group.
    Methods
    A total of 26 healthy young adults (n = 14 males; 12 females) completed the pre-assessment phase, and were randomly assigned to either intervention or control group. Physical activity, diet, and physical fitness (strength, cardiorespiratory fitness, and body composition) were assessed. Blood samples were collected at baseline, during and post one-bout of exercise, and baseline on sessions 1, 3, 6 and 9 of 3-week high intensity resistance training (3 times per week).
    Results
    None of the ANOVA effects on irisin concentration were significant after one-bout of exercise or 3 weeks of resistance training. The intervention group showed large significant changes from pre to post in relative body fat (%BF) (t (13) = -3.37, P = 0.003), and lean body mass (P = 0.016, d = 0.72). All muscle strength variables (1RM bench press (F (1,22) = 19.54, P
    Conclusions
    Serum irisin concentrations did not change during or post one-bout, nor during three-weeks of high-intensity resistance training compared to matched controls, while the program elicited significant changes in body composition and muscle strength in a group of healthy young adults. Only irisin levels in the control group were significantly increased. Additionally, no significant associations were found between irisin levels and physical activity, diet, or physical fitness. However, negative associations were found between baseline serum irisin concentrations and body composition (body weight and skeletal muscle mass) in males.
    Keywords: Irisin, High, Intensity, Resistance Training, Strength, Body Composition
  • Charles Ricardo Lopes, Alex Harley Crisp *, Brad Schoenfeld, Mayara Ramos, Moises Diego Germano, Rozangela Verlengia, Gustavo Ribeiro Da Mota, Paulo Henrique Marchetti, Marcelo Saldanha Aoki Page 2
    Objectives
    This study aimed to investigate the effect of different rest interval durations between sets during full-body resistance exercise sessions on total load lifted and blood lactate concentrations in resistance-trained individuals.
    Methods
    Ten healthy young men (age: 23 ± 6.5 years; total body mass: 82.8 ± 10.6 kg, height: 177.3 ± 0.1 cm) randomly performed 3 resistance exercise sessions with different rest intervals between sets (30 seconds, 60 seconds and 120 seconds). The resistance exercise sessions consisted of 6 full-body exercises (bench press; seated low row; shoulder press; back squat; leg press 45° and seated calf raise) performed with 4 sets of 10 repetitions maximum (RM). Total load lifted (sets × repetitions × load (Kgf)) and lactate blood concentration were determined for each exercise session. One way, repeated measures analysis of variance (ANOVA) followed by Bonferroni’s post-hoc test were used for multiple comparisons.
    Results
    The total load lifted was significantly (P
    Conclusions
    In conclusion, rest interval durations of 60 seconds and 120 seconds between sets favored a higher total load lifted in the exercise session when compared to the 30 seconds rest interval. The rest protocols implemented in the present study promoted a similar metabolic response (e.g. blood lactate concentration) to a full-body resistance exercise session in trained subjects.
    Keywords: Resistance Training, Rest Period, Volume Load, Metabolic Stress, Acute Response
  • Andre Aschmann, Beat Knechtle *, Vincent Onywera, Pantelis Theodoros Nikolaidis Page 3
    Previous research has indicated that sex, age and performance level of finishers influence pacing strategies in the marathon. However, the variation of pacing by country of origin and/or nationality of finishers has not been studied. The aim of this study, therefore, was to examine whether runners with different nationality differ in their pacing strategies. Data (women, n = 117,595; men, n = 180,487) from the ‘New York City Marathon’ between 2006 and 2016 were analysed. A small main effect of nationality on age was shown (P
    Keywords: Age, Running, Performance, Master Athlete, Endurance
  • Sai Aditya Krishna *, Thiagarajan Alwar, Anees Sayed, Gnanavel Mb, Arumugam Sivaraman Page 4
    Background
    Cricket is the most commonly played and followed sport in India. Modern day cricket demands a high level of consistent performance from the fast bowler, who carries the highest risk for injury. 3D motion analysis can be used to prevent injuries by identifying incorrect techniques. Researchers have identified key biomechanical variables as predictors of injury in fast bowlers. Very little such information is available with respect to Indian cricket fast bowlers despite the huge popularity of the sport here.
    Objectives
    To identify areas of injury risk in Indian fast bowlers with respect to key biomechanical variables, using 3D motion analysis.
    Methods
    22 male State level fast bowlers between ages 18 - 30 years underwent 3D motion analysis in an indoor cricket biomechanics testing facility. Bowling action was captured with a set of 3D cameras (250 fps) and 2D video cameras (125 fps). Data processing & analysis was done with proprietary software using a standard model. Key biomechanical variables including delivery Stride Length (SL), Lateral Trunk Flexion at Ball Release (LTF at BR) and Knee Flexion at Front Foot Contact (KF at FFC) were measured. Peak Vertical Ground Reaction Forces (pVGRF) were recorded simultaneously using force plates. Descriptive statistical analysis of results was done.
    Results
    A large proportion of bowlers were at risk of injuries (100% had less than optimum SL, 41% had high LTF at BR, 45% had high pVGRF and 45% had low KF at FFC). Bowling action type was found to be ideal or acceptable in 77%.
    Conclusions
    Indian fast bowlers, in spite of possessing less injurious bowling action types, are vulnerable to injury with respect to key biomechanical variables. This emphasises role of 3D motion analysis in Indian state level fast bowlers for early identification of injurious techniques and could have implications on coaching of fast bowlers in India.
    Keywords: Cricket, Fast Bowling, Cricket Injuries, Biomechanics
  • Claudio Chamorro *, Carlos De La Fuente, Daniel Jerez, Christian Campos, Luis Javier Chirosa Page 5
    Background
    The shoulder complex, because of its relatively extensive freedom of motion, offers a great variety of testing positions and articular planes for strength examination. Despite this, reliability of results are not clearly addressed. A novel pulley electromechanical dynamometer (FED) (functional electronic dynamometer) could be an alternative in strength assessment, however, the relative and absolute reliability have not been reported in the literature.
    Objectives
    To report the results of shoulder internal (IR) and rotators (ER) peak torque reliability in two assessment positions by FED in asymptomatic subjects.
    Methods
    Fifty-two healthy college students were included and tested twice within a two week period. In a supine position, the subjects randomly performed four isometric strength tests (i.e. IR at 40°, IR at 90°, ER at 40°, and ER at 90° of shoulder abduction).
    Results
    The intra-class correlation coefficients (ICC) for relative reliability at 90° were 0.96 (0.94 - 0.98) for IR and 0.94 (0.90 - 0.96) for ER. ICC at 40° were 0.89 (0.80 - 0.94) for IR and 0.97 (0.94 - 0.98) for ER. Absolute reliability expressed as standard error of measurement compared to the mean (SEM%) and 95% confidence interval (CI) of minimal detectable change percentage (MDC%) at 90° were 8.8% (-20.8, 28.4%) and 11.4% (-28.0, 35.2%) for ER. MDC% at 40° were 12.6% (-35.5, 34.8%) for IR and 18.1% (-28.1, 35, 2%) for ER.
    Conclusions
    Isometric strength testing protocol using FED showed an excellent reproducibility and can be safely used in clinical settings to monitor the strength changes in a group of individuals or in a single individual.
    Keywords: Muscle Strength Dynamometry, Reliability of Results, Rotator Cuff
  • Anjali Prajapat, Irshad Ahmad *, Zoya Khan, Kamran Ali, Mohd Ejaz Hussain Page 6
    Background
    Heart rate recovery (HRR) and heart rate variability (HRV) provide information about cardiac autonomic control; which indicates the physical fitness level of athletes in different sports.
    Objectives
    The purpose of our study was to compare HRR and HRV profiles in collegiate male soccer, field hockey and basketball athletes, at rest and following activity.
    Methods
    Fifty-five male collegiate athletes (20 soccer, 18 field hockey and 17 basketball players) were recruited on the basis of inclusion criteria and exclusion criteria. HRR was obtained following a bout of sub-maximal exercise on a treadmill. Measures of HRV were assessed at rest and during the last 5 minutes of a 15-min recovery period post-exercise.
    Results
    Soccer players showed the highest and basketball players recorded the lowest resting root mean square of successive differences (RMSSD). The value of RMSSD for basketball group was significantly lower than both soccer (P
    Conclusions
    The results of the present study suggest that basketball players exhibit greater sympathetic outflow, at rest and following activity. The autonomic profiles of soccer and field hockey players were found to be comparable.
    Keywords: Heart Rate, Sympathetic, Parasympathetic, Exercise
  • Luca Russo, Paolo Bartolucci, Luca Paolo Ardigò *, Johnny Padulo, Jelena Pausic, Antonio Dello Iacono Page 7
    Background

    This study aimed at investigating the acute effects of combined EXERCISE and TAPING in comparison to isolated proprioceptive exercise (EXERCISE) and ankle neuromuscular taping (TAPING) on one - leg stability performance in rugby players.

    Methods

    Stability tests, performed on a stabilometric platform, were assessed for stability before and after above interventions. Performed stability tests were one - leg static stance (dominant leg and non - dominant leg) each with eyes open and eyes closed. The assessed dependent variables were: centre of pressure (CoP) path length; CoP speed; medio - lateral, and anterior - posterior sway. Sixteen male rugby players (27.3 ± 3.3 years; 177.3 ± 7.3 cm; 88.8 ± 15.2 kg) from a non - professional rugby team were tested in all above conditions, according to a cross - over study design.

    Results

    Most of investigated variables improved following EXERCISE TAPING (CoP path length -18.2/ -15.6%, CoP speed -22.8/-17.7%, and anterior-posterior sway -21.0/ -16.3%), in comparison with the other two protocols. EXERCISE TAPING improved the stability control by combining the effects of both proprioceptive exercise and neuromuscular taping.

    Conclusions

    Such findings could suggest the benefits of planning long - term strategies using EXERCISE TAPING protocols for improving the functional stability and for preventing re - occuring injuries.

    Keywords: Ankle, Exercise, Proprioception
  • Alfredo Anderson Teixeira-Araujo, Louma, Iacute, Ra Carvalho Da Cruz, Fl, Aacute, Vio De Souza Araujo, Marcus Amando Fernandes Da Silva, Eduardo Miranda Dantas, Sergio Rodrigues Moreira * Page 8
    Background
    Both work activity and reduced nocturnal decrease in blood pressure (BP) are related to higher cardiovascular risk.
    Objectives
    The aim of the present study was to assess the blood pressure and autonomic responses of university professors during teaching and sleeping periods after different resistance exercise (RE) intensities.
    Methods
    Ten normotensive professors (33.6 ± 3.4 years, 82.4 ± 12.4 kg; 177.0 ± 7.5 cm; 26.2 ± 3.2 kg/m2) randomly underwent control (CONT) and RE before initiating their daily activities. RE consisted of a circuit training lasting 40 minutes at 40% and 80% of one repetition maximum test (40% 1RM and 80% 1RM). Systolic BP (SBP) and diastolic BP (DBP) as well as heart rate variability indicators in the time (RRi) and frequency domains (LF, HF, LF:HF ratio) were evaluated while resting and 24 hours after the sessions. The average day-period (DP), night-period (NP) and nocturnal BP fall (%NBPF) of SBP and DBP were calculated.
    Results
    During teaching, SBP (CONT: ∆ = 8.1 ± 9.1 mmHg; 40% 1RM: ∆ = 10.8 ± 10.5 mmHg and 80% 1RM: ∆ = 10.3 ± 7.9 mmHg; P 0.05). DBP showed different results to 40% 1RM (NT: 58.8 ± 5.1 mmHg and %NBPF: -24.2 ± 3.4 %; P
    Conclusions
    RE at 40% 1RM and 80% 1RM attenuated DBP values of subsequent teaching, however only 40% 1RM promoted better NT-BP and %NBPF values in university professors.
    Keywords: Post, Resistance Exercise Blood Pressure, Sympathovagal Balance, Professor
  • Takashi Abe *, Samuel L. Buckner, Kevin T. Mattocks, Matthew B. Jessee, Scott J. Dankel, J. Grant Mouser, Zachary W. Bell, Jeremy P. Loenneke Page 9
    Introduction
    World powerlifting records within the super heavyweight class are typically held by those with not only the greatest absolute muscle strength but also the greatest amount of skeletal muscle mass (SM).
    Case Presentation
    We examined the absolute and relative SM and muscle architecture of a 30 year old drug-free raw (i.e. without the use of powerlifting supportive equipment) powerlifter (1.84 m standing height and 183.1 kg body mass) who competes in the super heavyweight division and holds world records in the squat (477.5 kg), deadlift (392.5 kg), and total (1105 kg). Because the MRI magnet is too small for very large athletes, we used an ultrasound prediction equation to estimate SM. We also used ultrasound to determine muscle architecture (isolated muscle thickness, pennation angle and fascicle length). This powerlifter had large values of fat-free mass (138.6 kg) and total SM (58.0 kg) compared with previously published values. When calculating the powerlifting performance per unit SM, this lifter not only had high levels of absolute strength but also had high levels of relative strength per unit SM, particularly in the squat. Similarly, muscle thickness and pennation angle of the vastus lateralis were close to the highest values previously reported in the literature.
    Conclusions
    These results suggest that this powerlifter may be close to a physiologic limit with respect to muscle size and geometry.
    Keywords: Muscles, Ultrasonography, Human Limitation