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Context: The architectural characteristics of a muscle determine its function. Objective: To determine the architectural adaptations of the lateral gastrocnemius (LG) and medial gastrocnemius (MG) muscles after a functional eccentric strength training protocol consisting of heel drop exercises, followed by a subsequent detraining period. Design: Pretest and posttest. Setting: Training rooms and laboratory. Participants: The participants (N = 45) who were randomly divided into an experimental group (EG, n = 25) and a control group (CG, n = 20). Interventions: The 13-week intervention included participants (N = 45) who were randomly divided into an EG (n = 25) and a CG (n = 20). The EG performed a week of control and training, 8 weeks of eccentric training, and 4 weeks of detraining. The CG did not perform any type of muscular training. The architectural characteristics of the LG and MG muscles were evaluated at rest in both groups using 2-D ultrasound before (pretest–week 1) and after (posttest–week 9) the training, and at the end of the detraining period (retest–week 13). Main Outcome Measures: One-way repeated measures analysis of variance was used to determine training-induced changes in each of the variables of the muscle architecture. Results: After the training period, the members of the EG experienced a significant increase in the fascicle length of LG (t = −9.85, d = 2.78, P < .001) and MG (t = −8.98, d = 2.54, P < .001), muscle thickness (t = −6.71, d = 2.86, P < .001) and (t = −7.85, d = 2.22, P < .001), and the pennation angle (t = −10.21, d = 1.88, P < .05) and (t = −1.87, d = 0.53, P < .05), respectively. After the detraining period, fascicle length, muscle thickness, and pennation angle showed a significant decrease. In the CG, no significant changes were observed in any of the variables. Conclusions: The heel drop exercise seems to generate adaptations in the architectural conditions of LG and MG, which are also reversible after a detraining period. These results may have practical implications for injury prevention and rehabilitation programs.

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Grounds: The neck posture alterations can cause cervical pain and implicitly produce changes in the neck movement patterns, resulting in a greater risk of musculoskeletal disorders of the neck. The forward head position implies bending of the lower cervical spine and extension of the upper cervical spine. This is a common clinical observation in patients who have a sore neck and shoulders. The main objective of the study is to identify the relationship between the posture, the use of visual display units and physical activity in young adults. Method: This is a descriptive correlational study with a crossover design, with a sample of 26 university students. Data were collected from an ad-hoc questionnaire, physical activity habits questionnaire (SHRI) and a photogrammetry test processed by the postural assessment software (PAS). Results: Statistically significant differences were obtained between physical activity and the craniocervical angle (p = .007) and between the performance of physical activity of students pursuing different university degrees (p = .000). Conclusions: The practice of physical activity of moderate intensity can be a preventive factor for the forward head position.

BACKGROUND: Musculoskeletal pain represents a major public health problem. Workers who use visual display terminals (VDT) have suffered an increase in neck pain in recent decades. OBJECTIVE: The aim of this study was to analyze the relationship between physical activity (PA), sitting time, posture, and neck disability in a population of employed adults who use a computer at work. METHODS: In this descriptive-correlational study, 88 workers with a mean age of 48.31 years participated. All of the participants filled out the Self-Report Habit Index (SRHI), International Physical Activity Questionnaire (IPAQ), and neck disability index (NDI). The postural situation was also assessed with Posture Assessment Software (PAS/SAPO). RESULTS: A significant and inverse relationship was observed between the habit of PA practice and the Body Mass Index (BMI). A total of 59.1% of the participants have a moderate PA index. There was a statistically significant relationship between the NDI and the time that workers spend sitting in a workday. A significance level of p≤0.05 was established for all the statistical analyses. CONCLUSION: The increase in sitting time produces an increase in neck disability among workers and there are no significant differences between the level of PA and the cervical angles analyzed. The promotion of leisure-time PA and the reduction of prolonged uninterrupted sitting time at work could be one of the means to reduce musculoskeletal morbidity in the working population.