The influence of rest interval on total training load during 10 sets of the bench press exercise performed to concentric failure
Abstract
BACKGROUND: The resistance training variables which significantly affect the range of adaptive changes include the rest interval (RI) and volume of total lifted load. The length of the rest interval is highly dependent on the training objective, training status and exercise volume.
Therefore the main objective of the research was the evaluation of 3 different rest intervals (2, 4, and 6 min) on total volume load in a 10 set training session of the bench press (BP) exercise performed with a load of 60% 1 RM to concentric failure. METHODS: Ten male athletes (age, 32 +/- 4.6 years, body mass 86.3 +/- 5.2 kg, body height 181.3 +/- 4.2 cm) performed 10 sets of the BP with a load of 60% 1 RM until concentric failure on 3 occasions, with 2-, 4- and 6-minute rest intervals.
Capillary blood samples were taken for the analysis of lactate concentration (LA) and blood pH. The samples were taken at rest, and approximately one minute after the cessation of the 3rd, 6th and 10th set.
RESULTS: Using shorter RI (2 min) in multiple sets performed to concentric muscular failure highly stressed the glycolytic system, which is evidenced by highest post exercise LA and significantly lowered blood pH (P<0.001). This may be beneficial for the development of local muscular endurance.
On the other hand, longer (6 min) RI may create conditions for a higher volume of total workload and adaptive changes directed at strength and hypertrophy. CONCLUSIONS: The rest intervals of 4 and 6 minutes allow lifting of high loads without significant metabolic acidosis in the last sets, therefore useful for the development of maximum strength and hypertrophy.
The rest interval of 2 minutes decreases the training workload with higher LA in the last sets of the BP exercise, therefore this rest interval can stimulate strength endurance and glycolytic metabolism.