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Whole body vibration (WBV) during exercise offers potential to augment the effects of basic exercises. However, to date there is limited information on the basic physiological and biomechanical effects of WBV on skeletal muscles. ...
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Whole body vibration (WBV) during exercise offers potential to augment the effects of basic exercises. However, to date there is limited information on the basic physiological and biomechanical effects of WBV on skeletal muscles. The aim of this study was to determine the effects of WBV (40. Hz, 1.9. mm synchronous vertical displacement) on the myoelectrical activity of selected plantarflexors during heel raise exercise. 3D motion capture of the ankle, synchronised with sEMG of the lateral gastrocnemius and soleus, was obtained during repetitive heel raises carried out at 0.5. Hz on 10 healthy male subjects (age 27 ± 5 years, height 1.78 ± 0.04. m, weight 75.75 ± 11.9. kg). During both vibration and non vibration the soleus activation peaked earlier than that of the lateral gastrocnemius. The results indicate that WBV has no effect on the timing of exercise completion or the amplitude of the lateral gastrocnemius activity, however significant increases in amplitudes of the soleus muscle activity (77.5-90.4% MVC P< 0.05). WBV had no significant effect on median frequencies of either muscle. The results indicate that the greatest effect of WBV during heel raise activity is in the soleus muscles during the early phases of heel raise.
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Between October 1996 and October 1997, three calf raising systems and their effect on improved milk production in dual-purpose systems were evaluated on four farms located in Peru's Ucayali region, along the Federico Basadre road,...
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Between October 1996 and October 1997, three calf raising systems and their effect on improved milk production in dual-purpose systems were evaluated on four farms located in Peru's Ucayali region, along the Federico Basadre road, between kilometers 64 and 78. Prevailing soils were UItisols, with acid pH, high interchangeable Al content, Iow base saturation, and low N, P, K, S, and OM contents. The treatments studied were as follows: T_1 = complete separation of calf from its mother and grazing in paddocks of S. guianensis, restricted suckling, and residual milk; T_2 = similar to T_1 plus supply of concentrate; and T_3 = improved control, consisting of calf remaining 8 h with its mother, followed by grazing on S. guianensis. The last two treatments were studied on one farm, and two factors were studied on another farm as follows: (a) hours of permanence of calf with its mother (0.5 and 1 h) and (b) amount of milk provided to calf after milking (residual milk and access to a non-milked teat). The variables evaluated were live weight gain of calf, salable milk, total milk, cost of technology, parasitic rate, and sanitary condition. Treatments were distributed using three designs: a Latin square design, a completely randomized design, and completely randomized design with factorial arrangement. Live weight gains in the treatment with concentrate were significantly superior (P 收起
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Background: Whether an Achilles tendon rupture is treated surgically or not, complications such as muscle weakness, decrease in heel-rise height, and gait abnormalities persist after injury. Purpose: The purpose of this study was ...
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Background: Whether an Achilles tendon rupture is treated surgically or not, complications such as muscle weakness, decrease in heel-rise height, and gait abnormalities persist after injury. Purpose: The purpose of this study was to evaluate if side-to-side differences in maximal heel-rise height can be explained by differences in Achilles tendon length. Study Design: Case series; Level of evidence, 4. Method: Eight patients (mean [SD] age of 46 [13] years) with acute Achilles tendon rupture and 10 healthy subjects (mean [SD] age of 28 [8] years) were included in the study. Heel-rise height, Achilles tendon length, and patient-reported outcome were measured 3, 6, and 12 months after injury. Achilles tendon length was evaluated using motion analysis and ultrasound imaging. Results: The Achilles tendon length test-retest reliability (intraclass correlation coefficient = 0.97) was excellent. For the healthy subjects, there were no side-to-side differences in tendon length and heel-rise height. Patients with Achilles tendon ruptures had significant differences between the injured and uninjured side for both tendon length (mean [SD] difference, 2.6-3.1 [1.2-1.4] cm, P = .017-.028) and heel-rise height (mean [SD] difference, 4.1 to 6.1 [1.7-1.8] cm, P = .012-.028). There were significant negative correlations (r = 20.943, P = .002, and r = 20.738, P = .037) between the side-to-side difference in heel-rise height and Achilles tendon length at the 6- and 12-month evaluations, respectively. Conclusion: The side-to-side difference found in maximal heel-rise height can be explained by a difference in Achilles tendon length in patients recovering from an Achilles tendon rupture. Minimizing tendon elongation appears to be an important treatment goal when aiming for full return of function.
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Purpose: To determine the validity of the single limb heel raise (SLHR) test as a potential screening tool to detect lower extremity disability in patients with sporadic inclusion body myositis (sIBM). Methods: We compared gait sp...
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Purpose: To determine the validity of the single limb heel raise (SLHR) test as a potential screening tool to detect lower extremity disability in patients with sporadic inclusion body myositis (sIBM). Methods: We compared gait speed and fall history between subjects with sIBM who either could complete one SLHR (SLHR group) or could not complete one SLHR. Discriminative validity was established by comparing between group differences in functional measures based on group assignment. Receiver operating characteristics curve analysis was used to determine the predictive validity of completing one repetition on the SLHR test. Spearman correlations were used to determine the association between gait kinematics and number of repetitions achieved on the SLHR test. Results: Forty-three subjects (13 females) were studied. The SLHR group (n = 21) showed significantly greater gait speed (p<0.001) and decreased gait aid use (p<0.05) compared to the no SLHR group (n = 22). SLHR cut scores of 1, 20, and 22 repetitions maximized positive likelihood ratios (+LR) for the ability to walk at 54.9 (+LR. 2.2), 63.2 (+LR. 9.5), and 73.1 m/min (+LR. 5.0), respectively. Conclusion: The SLHR test demonstrates adequate discriminative and predictive validity as a screening tool for lower extremity disablement in patients with sIBM.
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The production of calves raised on cattle depends on mother cows and the direct market. The calves mainly live on mother's milk, some cattle fodder and a little grain from the farm. Out of this reason and because of the high quali...
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The production of calves raised on cattle depends on mother cows and the direct market. The calves mainly live on mother's milk, some cattle fodder and a little grain from the farm. Out of this reason and because of the high quality of the product it has a high reputation for the consumer. Some other advantages are for the method, the producer and the national economy because animals are used very young and though they decrease the mass of beef.
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This article details a 6-week resistance training program that can be used to improve sprint acceleration in amateur athletes. This program can concurrently enhance base lower-body strength and 10-m speed and incorporates the back...
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This article details a 6-week resistance training program that can be used to improve sprint acceleration in amateur athletes. This program can concurrently enhance base lower-body strength and 10-m speed and incorporates the back squat, step-up, cable hip flexion, and smith machine calf raise loads can be increased from approximately 75-90% of one repetition-maximum over the course of the program. The exercises are described with supporting scientific evidence for their use additionally, suggestions are provided as to how the program could be modified and progressed with different exercises to further enhance the force-velocity profile.
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