The hypothalamus is under the control of several “higher” brain centres and several neurotransmitters 13 known to play a major role in various neuroendocrine and behavioural functions, for example, activation of the HPA axis, feeding and locomotion.14 Therefore, the typical HPA axisrelated hormones cortisol, adrenocorticotrophic hormone (ACTH), prolactin (PRL) and human growth hormone (GH) were targeted in the present study.
The plank is a yoga position that is basically a push up at the top of the action; you're suspending your body in a straight line from your toes while holding your body at an incline with your arms pressing straight up from the ground. Better yet, you're squeezing your abdominal muscles while you're holding the position. This works the transverse abdominis, the deepest-lying of the abdominal muscles. Though not visible, strengthening it will enhance your core stability and posture, both of which add to the effect of an upright profile.
Torque signal and knee angle signal were recorded using the same dynamometer as for the OLDE (Cybex NORM isokinetic dynamometer, CMSi, Computer Sports Medicine Inc., Stoughton, USA). During the tests a two shoulder harnesses and a belt across the abdomen limited extraneous movement of the upper body. Torque signal and knee angle signal were digitized on-line at a sampling frequency of 1 kHz using a computer, and stored for analysis with commercially available software. Torque signal was filtered prior to data analysis (Butterworth low-pass filter at 100 Hz). Torque signal, knee angle signal and EMG signal were recorded with the same device (MP150, Biopac Systems Inc., Goleta, USA) and analyzed with the same commercially available software (Acqknowledge 4.2 for MP Systems, Biopac Systems Inc., Goleta, USA).
Exclusion criteria included major diseases or conditions such as severe heart disease, uncontrolled hypertension, obesity, osteoarticular pathology, and neurological disease. Criteria were evaluated on the basis of clinical history, resting ECG, and physical examination. Participants maintained their lifestyles and were instructed not to take part in any other physical programs throughout the study. At the time of the initial design, the study consisted of a 12-week randomized controlled trial with a frequency of 3 times a week, 36 sessions in all, ending with a new assessment of their wellness and the potential persistence of the results on functional/physical capacities.