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Purpose: The purpose of the present research was to investigate the effect of eight weeks of progressive resistance exercise and a subsequent detraining period on the indicators of muscle fiber shortening (FS%) and the relative wall thickness (RWT) of the left ventricle in low-mobility women. Method: This semi-experimental study was conducted in a field-laboratory setting. A total of 32 sedentary women, who met the criteria for participation and were able to engage in the exercise protocol, were randomly assigned to two groups: 1) Resistance training group (16 participants), and 2) Control group (16 participants). Anthropometric characteristics, body composition, and structural indices such as left ventricular muscle fiber shortening percentage (FS%) and relative wall thickness (RWT) were measured using an echocardiography device at three intervals: before the start of training, at the end of 8 weeks of training, and after a 4-week detraining period. The training protocol was implemented over 12 weeks, consisting of 8 weeks of training with three sessions per week, followed by 4 weeks of detraining. Data were analyzed using independent t-tests and repeated measures analysis of variance (ANOVA) at a significance level of p < 0.05, using SPSS version 21. Results: The results showed a significant difference in FS% between pre-test and post-test measurements for both the experimental and control groups (p < 0.05). Additionally, a significant decrease in FS% was observed in the training group during the detraining period (p < 0.05). Similarly, a significant change in RWT was found between pre-test and post-test measurements in both groups (p < 0.05), and significant changes in RWT were also observed during the detraining period in the training group (p < 0.05). Conclusion: Based on these findings, it can be concluded that 8 weeks of resistance training led to beneficial changes in the structure and function of the heart in sedentary women. However, the 4-week detraining period resulted in negative effects on these adaptations. Therefore, it is recommended that individuals engage in regular and structured resistance training to maintain these positive adaptations.

This study aimed to investigate the resilience of sports clubs as business enterprises in the crisis caused by the Coronavirus epidemic. Thirty-five experts in the field of sports club management were interviewed in three rounds of interviewing. In the first round, the main questions for the interview was determined, and then two series of interviews were carried out with experts. Basis of the analysis in the second one was content analysis approache. A summary of the answers given to the sample and interviewing were conducted again. Kolmogorov-Smirnov and one-sample t-tests were used to measure the resilience. In the next study section, the propulsive forces identified with the Delphi technique and prioritized based on the degree of importance and uncertainty, and Micmac was used to write possible scenarios. Results indicated that resilience of sports clubs was not in a good condition in the presence of crises and challenges. The findings showed that poor management of sports clubs and low income were the most influential critical factors in resilience. A low partnership index with a total of 201619 had the highest impact. Organizations that responded quickly and actively and were user-friendly under adverse economic conditions were more likely to succeed.