The relationship between physical activity and quality of life during the confinement induced by COVID-19 outbreak: a pilot study in Tunisia

The present study aimed to determine the relationship between physical activity (PA) and quality of life (QoL) during the confinement caused by the COVID-19 outbreak. 216 participants (men: n = 112, women: n= 114) were included in the present study. They were divided into three groups (i.e., inactive group [IG]: less than 600 Metabolic Equivalent of Tasks (METs), n = 131; minimally active group [MAG]: from 600 to 2999 METs, n = 49; and health-enhancing PA group [HEPAG]: 3000 + METs, n = 36) based on their habitual PA level in the period of confinement. World Health Organization Quality of Life Instrument-Short Form (WHOQOL-Bref) and International Physical Activity Questionnaire-Bref (IPAQ-Bref) questionnaires were used to assess QoL and PA intensities. The main findings of the present study showed that MAG and HEPAG have better total PA, physical, psychological, social, and environmental QoL domains scores than IG (all, p<0.01). Small to large correlations (r ranging 0.14-0.72) were also observed between total PA, total walking activity, total moderate-intensity PA, total vigorous-intensity PA and QoL domains (all, p<0.01). PA with light- moderate- and vigorous intensities can be well recommended to decrease the negative psychosocial effect of confinement. However longitudinal studies are needed to draw causal inferences and underpin more robust and evidence-based and informed recommendations

Effects and Dose-Response Relationships of Motor Imagery Practice on Strength Development in Healthy Adult Populations: a Systematic Review and Meta-analysis.

BACKGROUND: Motor imagery (MI), a mental simulation of a movement without overt muscle contraction, has been largely used to improve general motor tasks. However, the effects of MI practice on maximal voluntary strength (MVS) remain equivocal. OBJECTIVES: The aims of this meta-analysis were to (1) estimate whether MI practice intervention can meaningfully improve MVS in healthy adults; (2) compare the effects of MI practice on MVS with its combination with physical practice (MI-C), and with physical practice (PP) training alone; and (3) investigate the dose-response relationships of MI practice. DATA SOURCES AND STUDY ELIGIBILITY: Seven electronic databases were searched up to April 2017. Initially 717 studies were identified; however, after evaluation of the study characteristics, data from 13 articles involving 370 participants were extracted. The meta-analysis was completed on MVS as the primary parameter. In addition, parameters associated with training volume, training intensity, and time spent training were used to investigate dose-response relationships. RESULTS: MI practice moderately improved MVS. When compared to conventional PP, effects were of small benefit in favour of PP. MI-C when compared to PP showed unclear effects. MI practice produced moderate effects in both upper and lower extremities on MVS. The cortical representation area of the involved muscles did not modify the effects. Meta-regression analysis revealed that (a) a training period of 4 weeks, (b) a frequency of three times per week, (c) two to three sets per single session, (d) 25 repetitions per single set, and (e) single session duration of 15 min were associated with enhanced improvements in muscle strength following MI practice. Similar dose-response relationships were observed following MI and PP. CONCLUSIONS: The present meta-analysis demonstrates that compared to a no-exercise control group of healthy adults, MI practice increases MVS, but less than PP. These findings suggest that MI practice could be considered as a substitute or additional training tool to preserve muscle function when athletes are not exposed to maximal training intensities