Self-regulation and self-control in exercise: The strength-energy model

Self-regulation is an important component of psychosocial theories of exercise behaviour and lack of self-regulatory skills are associated with low adherence to health-related exercise. This review presents a strength-energy model of self-control as an explanation of self-regulation in exercise contexts. The review will provide impetus for original research aimed at understanding exercise behaviour and help develop recommendations for exercise promotion. In the model, self-control is conceptualized as a global but limited resource. Engaging in actions requiring self-control depletes resources leading to self-regulatory failure. Self-control resource depletion is reduced through rest and frequent training on self-control. The expectation of the need to exert self-control in future leads to a conservation of self-control resources. Proposed mechanisms for self-control resource depletion include changes in physiological markers and blood glucose levels. Based on our review, we propose an integrated model of self-regulation incorporating hypotheses from the strength-energy model with those from traditional psychosocial models of exercise behaviour. Recommendations for future research include incorporating hypotheses from the strength-energy model into theories of self-presentation and interpersonal relations in exercise. Practical recommendations aimed at minimising self-control depletion in exercise include the provision of advice on nutrition and recovery, self-control training and motivational and implementation intention strategies

Efficacy of Withania somnifera supplementation on adult’s cognition and mood

The present study examined the effects of a proprietary Ashwagandha (Withania somnifera) root and leaf extract (NooGandha® Specnova LLC, USA) supplement for improving cognitive abilities, cortisol levels, and self-reported mood, stress, food cravings, and anxiety with adults who have perceived stress. Healthy adults (n = 43 women and n = 17 men; mean age = 34.41 years) who reported experiencing perceived stress were randomized to the following groups: Ashwagandha (400 mg/d), Ashwagandha (225 mg/d), and placebo for 30 days. The following outcomes were assessed at Day 0, Day 15, and Day 30: saliva cortisol levels, cognitive performance (i.e., CNS vital signs), and the self-reported measures of Trait Anxiety Inventory, Depression Anxiety Stress Scale, Perceived Stress Scale, and Food Cravings Questionnaire-15. For the self-report assessments, significant main effects for time were evidenced for anxiety, depression, perceived stress, and food cravings, p's < 0.01. The main effect for group and the interactions were non-significant. For the CNS vital signs, significant differences were observed in cognitive flexibility, visual memory, reaction time, psychomotor speed, and executive functioning, p's < 0.05, with the Ashwagandha groups often out-performing the placebo group. Both Ashwagandha groups had reductions in cortisol levels over time, with significant reductions evidenced for the Ashwagandha 225 mg/d group from Day 0 to Day 15 to Day 30. The placebo group had a non-significant increase in cortisol levels from Day 0 to Day 15–30. No adverse events were reported. In conclusion, Ashwagandha supplementation may improve the physiological, cognitive, and psychological effects of stress