Froude Efficiency and Velocity Fluctuation in Forearm-Amputee Front Crawl: Implications for Para Swimming Classification.

PURPOSE: The impact of physical impairment on Froude efficiency and intracyclic velocity fluctuation in Para swimmers is not well documented. Identification of differences in these variables between disabled and nondisabled swimmers could help develop a more objective system for assigning Para swimmers to classes for competition. This study quantifies Froude efficiency and intracyclic velocity fluctuation in unilateral forearm-amputee front crawl swimmers and evaluates associations between these variables and performance. METHODS: Ten unilateral forearm-amputee swimmers completed front crawl trials at 50- and 400-m pace; three-dimensional video analysis provided mass center, and wrist and stump velocities. Intracyclic velocity fluctuation was calculated as follows: 1) maximum-minimum mass center velocity, expressed as percent of mean velocity, and 2) coefficient of variation in mass center velocity. Froude efficiency was the ratio between mean swimming velocity and wrist plus stump velocity during each segment's respective 1) underwater phase and 2) propulsive underwater phase. RESULTS: Forearm amputees' intracyclic velocity fluctuation (400 m: 22% ± 7%, 50 m: 18% ± 5%) was similar to published values for nondisabled swimmers, whereas Froude efficiencies were lower. Froude efficiency was higher at 400-m (0.37 ± 0.04) than 50-m pace (0.35 ± 0.05; P < 0.05) and higher for the unaffected limb (400 m: 0.52 ± 0.03, 50 m: 0.54 ± 0.04) than the residual limb (400 m: 0.38 ± 0.03, 50 m 0.38 ± 0.02; P < 0.05). Neither intracyclic velocity fluctuation nor Froude efficiency was associated with swimming performance. CONCLUSIONS: Froude efficiency may be a valuable measure of activity limitation in swimmers with an upper limb deficiency and a useful metric for comparing swimmers with different types and severity of physical impairment.

The effects of 12 weeks' resistance training on psychological parameters and quality of life in adults with Facioscapulohumeral, Becker, and Limb-girdle dystrophies.

PURPOSE: Investigate the impact of 12-weeks' moderate-intensity resistance training on psychological parameters in ambulatory adults with Facioscapulohumeral, Becker, and Limb-girdle muscular dystrophy. METHODS: Seventeen adults with Facioscapulohumeral (n = 6), Limb-girdle (n = 6; types 2A, 2B, 2L, and 2I), or Becker (n = 5) muscular dystrophy took part. Participants were tested at baseline (PRE), after a 12-week control period (PRE2), and after a 12-week supervised resistance training programme (POST). Training included multi-joint and single-joint resistance exercises. Outcomes from self-report questionnaires were health-related quality of life, depressive symptoms, trait anxiety, self-esteem, and physical self-worth. RESULTS: No difference in outcome measures, except depressive symptoms, was found in the control period (PRE to PRE2). Symptoms of depression were reduced by 9% from PRE to PRE2 (p < 0.05) and by a further 19% from PRE2 to POST (p < 0.05). Other changes from PRE2 to POST were that trait anxiety reduced by 10%, self-esteem increased by 10%, physical self-worth increased by 20%, and quality of life improved in 8 domains (p < 0.05). CONCLUSION: These findings demonstrate the positive impact of moderate-intensity resistance training on psychological health and quality of life in adults with Facioscapulohumeral, Becker, and Limb-girdle muscular dystrophies.Implications for rehabilitationResistance training can have a positive impact on psychological health and quality of life in adults with Facioscapulohumeral, Becker, and Limb-girdle muscular dystrophy.Healthcare professionals should consider including moderate-intensity resistance training within the management and treatment programmes of adults with Facioscapulohumeral, Becker, and Limb-girdle muscular dystrophy.

Psychological parameters impact health-related quality of life in mental and physical domains in adults with muscular dystrophy.

The impacts of potentially treatable psychological parameters on quality of life are relatively unreported in adults with Facioscapulohumeral, Becker and Limb-girdle muscular dystrophy. The purpose of this study was to compare quality of life, psychological parameters, and physical function between adults with muscular dystrophy and controls, and to examine relationships among these parameters in muscular dystrophy. Twenty-one adults with muscular dystrophy (n = 7 Becker, n = 8 Facioscapulohumeral, n = 6 Limb-girdle) and ten age-matched controls participated. Outcome measures were health-related quality of life, depressive symptoms, trait anxiety, self-esteem, physical self-worth and six-minute walk distance. Quality of life scores were lower in the muscular dystrophy groups than the control (p < .05). Depressive symptoms had the greatest association with quality of life in the Mental Health domain (r= -0.89, p < .001). Depressive symptoms also had the most associations with quality of life (7 of 10 domains), followed by trait anxiety (6 of 10 domains), physical self-worth (5 of 10 domains), self-esteem (4 of 10 domains) and six-minute walk distance (3 of 10 domains). Psychological parameters and, to a lesser extent, physical function impact quality of life in muscular dystrophy. This study provides a rationale to include psychological assessment and treatment within muscular dystrophy healthcare.

Biomechanical Response to Acute Stretching in Dancers and Non-Dancers.

This study aimed to investigate the bio- mechanical response of the hamstring muscles to acute stretching in dancers (D) compared to non-dancers (ND). Maximal range of motion (ROMMax) and stiffness of the hamstrings were assessed in 46 young males, 23 undergraduate students (ND) and 23 professional dancers (D). Ages of the two groups were D 21.5 ± 0.60 years; ND 27.5 ± 0.98 years). Testing was performed in two sessions, familiarization with procedures in the first session and the tests themselves (pre- and post-test and intervention) in the second, with a 24- to 48-hour interval between. The pre-test consisted of three trials of passive knee extension to the point of increased tension in the hamstrings, defined as ROMMax. The resistance torque recorded at ROMMax was defined as torqueMax. Six 30-second constant torque stretches were performed at 100% of the torqueMaxreached in the pre-test in one lower limb only (intervention), with the contralateral limb used as control. The torque measured at an identical ROM before (pre-test) and after (post-test) the intervention was defined as torqueROM, and represented stiffness in this study. Reliability of the ROMMax, torqueMax, and torqueROMwas assessed via intraclass correlation coefficients (ICC3, k) and standard error of the measurements (SEM). Comparison between dancers and non-dancers, control, and intervention conditions for all dependent variables was performed using ANOVA repeated measures followed by Tukey post hoc comparisons to highlight any interaction. The submaximal stretch intensity applied caused torqueROM to decrease in both D and ND groups (p < 0.01), indicating a decrease in stiffness, but no difference between the groups was found. A significantly greater increase in ROMMax was found for the D group compared to the ND group (p < 0.01), suggesting that other aspects in addition to MTU biomechanical adaptations may have played a role in the ROMMax increase, especially for the D group. Further research is needed to explore what those other adaptations are. Meanwhile, coaches and physical therapists should be aware that dancers may require different stretch training protocols than non-dancers.

The Effects of Resistance Exercise Training on Strength and Functional Tasks in Adults With Limb-Girdle, Becker, and Facioscapulohumeral Dystrophies.

Background: The inclusion of resistance training in the treatment and management of muscular dystrophy has previously been discouraged, based on mainly anecdotal evidence. There remains a lack of experimental investigation into resistance training in individuals with muscular dystrophy. The aim of the current study was therefore, to determine the effect of a 12-week resistance training programme on muscle strength and functional tasks in ambulatory adults with muscular dystrophy. Methods: Seventeen ambulatory adults with muscular dystrophy (Facioscapulohumeral muscular dystrophy: n = 6, Limb-Girdle muscular dystrophy: n = 6, Becker muscular dystrophy: n = 5) were recruited for this study. Participants attended three testing sessions: one session at baseline, one session after a 12-week control period and one session after a 12-week resistance training period. Each testing session consisted of measurements of isometric knee extensor and knee flexor maximum voluntary contraction (MVC) torque (Cybex dynamometer). Participants also completed a timed sit-to-stand, a four steps-stair ascent, and a four steps-stair decent. The 12-week resistance training period consisted of two supervised sessions a week. Each training session included a 5-min warm-up, a step-up exercise, free-standing or assisted squats, knee flexion and knee extension exercises, and an additional 6 single-joint exercises specific to each individual's needs. Results: Knee flexor MVC torque increased by 13% after the 12-week resistance training programme (p < 0.05), with no change over the control period. Knee extensor MVC torque did not significantly change after the training programme or the control period. Time taken to complete sit-to-stand, stair ascent and stair descent all decreased (improved) following the 12-week training programme (p < 0.05). Conclusions: A twice-a-week, 12-week, resistance training programme resulted in increased knee flexion strength and improvements in functional tasks in ambulatory adults with muscular dystrophy. This provides support for the inclusion of resistance training in the treatment programmes for these forms of muscular dystrophy.