## 2 Materials and Methods
### Procedures  
Familiarization: The subjects performed familiarization sessions before the testing sessions. A standardized warm-up was performed before each familiarization and testing session [28]. On Wednesday of the familiarization week, the subjects performed back squats with weight releases (Rogue; Columbus, OH, USA) to better prepare them for training with this equipment. The weight releases were adjusted in length, so their loads were released during squats at a parallel position and during bench press as soon as the bar touched the chest. The subjects performed several sets with low repetitions (2-3) with 50% of their 1 RM loaded on the weight releases that would detach upon completing the eccentric movement. A similar process with the weight releases was used for the bench press on Friday. Testing: The subjects underwent a testing week after the familiarization week (pre-tests) and after the final week of training (post-tests). The subjects performed the testing sessions at the same time of day during the pre- and post-test sessions. Before any testing was performed, the subjects had to be reasonably hydrated (USG < 1.020) as assessed by using a refractometer (Atago Co., Ltd., Tokyo, Japan) to test urinary-specific gravity [29]. Once this criterion was met, the blood samples were collected Monday morning between 6:00 and 8:00 am after an overnight fasting (\(\geq\)8 hrs). The blood samples were obtained from the antecubital vein by a licensed phlebotomist. The samples were collected into serum separator tubes (BD Vacutainer, Becton, Dickinson and Company, Franklin Lakes, NJ, USA) and left to clot for 20 min after being drawn. After clotting, the blood samples  
Figure 1: Methodology flowchart. were centrifuged (VanGuard V6000, SmithKline Beecham Clinical Laboratories, Montvale, NJ, USA) and the serum was stored at -70 \({}^{\circ}\)C (So-Low, Environmental Equipment Co., Inc., Cincinnati, OH, USA) until the analyses. The blood collection and preparation process were repeated post-training. For the hormonal concentration analyses, the serum samples were thawed to room temperature and gently mixed. The serum samples were analyzed at a Medical School Clinical Reference Laboratory using the Siemens Atellica IM Analyzer 1300 (Simens Healthcare Diagnostics INC, Walpole, MA, USA). After the blood samples were collected, the subjects' body mass and body composition were assessed using SECA mBCA 514 (Seca Medical Scales, Chino, CA, USA). All the analyses were performed in duplicates, and the average of two readings was used in the statistical analyses. The CV for these variables in this Reference laboratory was less than 2%. The maximum dynamic strength was measured via 1 RM test for the back squat (Monday) and bench press (Wednesday) using the protocol described by [PERSON] et al. [PERSON] et al. (2019). The isometric mid-thigh pull (IMTP) testing took place on Friday using the protocol described by [PERSON] et al. [PERSON] et al. (2019). Following a standardized warm-up, each subject was positioned in a custom-built power rack with an affixed bar. The subjects' internal knee and hip angles were measured manually using a goniometer and were required to be 130 \(\pm\) 5\({}^{\circ}\) and 150 \(\pm\) 5\({}^{\circ}\), respectively. Each power rack contained dual force plates (2 \(\times\) 91 cm \(\times\) 45.5 cm) with sampling at 1000 Hz (Rice Lake Weighing Systems, Rice Lake, WI, USA). The subjects were secured to the bar using straps and athletic tape to eliminate grip strength as a confounding variable during testing. Prior to the maximal trials, a 50% and a 75% warm-up effort was completed, separated by sixty seconds of rest. Three minutes of rest was given following the final warm-up effort. Each subject completed two maximal-effort IMTP trials and was instructed to \"pull as fast and as hard\" as they could. Additional trials were completed if the IPF differed >250 N between the pull trials or if it differed >200 N in any counter-movement trial. Verbal encouragement was provided during every IMTP effort.