Acute metabolic responses following different resistance exercise protocols

Resistance exercise (RE) can be an excellent modality for glycemic control. Studies have demonstrated that a single RE session can reduce glycemia in subjects with or without diabetes. Little is known about the dose-response effect of RE on glycemic control. This study aimed to investigate the acute metabolic responses after different RE protocols. Eighty-nine males were separated into six groups that completed RE protocols: 2 sets of 18 repetitions (2 x 18 at 50% of 1-repetition maximum (1RM); n = 19); 3 sets of 12 repetitions (3 x 12 at 70% of 1RM; n = 14); 4 sets of 9 repetitions (4 x 9 at 80% of 1RM; n = 13); 6 sets of 6 repetitions (6 x 6 at 90% of 1RM; n = 19); circuit (2 x 18 at 50% of 1RM; n = 12); and a control session (n = 12). The exercise sequence consisted of 8 exercises. An oral glucose tolerance test was conducted with metabolic measurements immediately after each RE protocol and every 15 min until 120 min of recovery. All groups exhibited significantly lower values (p < 0.05) in the glucose area under the curve (AUC) when compared with control over a 120 min monitoring period. The 6x6 group showed a significantly lower glucose AUC versus the 3 x 12 and 4x9 groups (p = 0.004; p = 0.001, respectively). As for blood lactate, the control and 6x6 groups exhibited lower AUC values versus all other groups (p < 0.05), and AUC for glucose and lactate concentration showed a negative and significant correlation (r = -0.46, p < 0.0001). It appears that a combination of 9-12 repetitions per set and 3-4 sets per muscle group might be optimal for acute postprandial glucose control.