A total of 136 male and female adults, members of local gyms, were initially invited for participation in the study after giving their written consent. After a second contact with the participants, forms regarding the inclusion and exclusion criteria were sent for completion.~Of the 136 that initially answered positively for participation, 62 did not meet the inclusion criteria, based on their reports and the clinical examination by a health professional. Of the remaining 74 participants, 32 were excluded because of previous low back pain incidents and other recent musculoskeletal injuries that led to rehabilitation, while 22 decided to not participate for personal reasons.~The remaining 20 participants were randomly allocated to either training group or intervention group, by a neutral, blinded investigator who had no involvement and was unaware of the study purposes. The intervention group will be trained and supervised by a certified fitness instructor in a gym class, who will be responsible for the correct execution of the exercises. The duration of the intervention will be 5 weeks, 3 times a week.
This study aims in investigating the effects of a core muscles' strengthening program on core muscles' atrophy and contraction ability. Twenty healthy adults recruited and randomly assigned to either a 5-week training group developed to activate and strengthen local trunk muscles or a control group. The training program includes isometric bridging exercises from various positions and dynamic exercises for lumbopelvic stability. Core muscles' thickness will be assessed at rest and contracting conditions, prior and after the intervention, using ultrasonography.