Participants The study included a total of 47 subjects, (29 females, 18 males) ages 65 to 75 years, recruited from an elderly social club. The participants were divided into two groups: experimental group (n=27; 10 men and 17 female) and control group (n=20; 8 men and 12 female). The sampling was natural and intentional. All subjects originated from Murcia (Spain) and met the following inclusion criteria: had never previously attended classes in fitness academies or were not currently performing regular physical activity, and had no previous experience with resistance-training programmes. Exclusion criteria included any history of neuromuscular, metabolic, hormonal or cardiovascular diseases; not taking any medication that could influence hormonal and neuromuscular metabolism. In addition, the participants were advised to not alter their diet during the study. Participants were informed about the possible risks and discomforts that could arise and were asked to complete a health history questionnaire and sign a consent form. The current study was approved of the Ethics Committee of the Catholic University San Antonio of Murcia (Spain) following the guidelines of the Helsinki Declaration.