Comparison of hematologic response between trained and sedentary volunteers after high-intensity resistance exercises

Introduction: Hematological changes associated with high-intensity physical exercise remain controversial. Objective: To compare hematological responses between practitioners and sedentary volunteers following a high-intensity resistance exercise (RE) session. Methodology: Twenty-four healthy men participated in the study (pre–post with non-randomized parallel groups), including 14 sedentary (SG) individuals and 10 bodybuilding practitioners (+3x per week) for more than six months (PG). The 10RM test (leg extension, squat, and leg press) was used to determine the training load. The exercise session consisted of four sets of 10RM for each exercise, with 1-minute rest intervals between sets and 2 minutes between exercises. Blood samples were collected before and immediately (0min) after the RE session for erythrogram and leukogram analyses (absolute values and relative values [%]). Results: RE increased the absolute values of the variables analyzed in both groups. Neutrophil counts were 13% (95%CI: 5 to 20%) higher in the PG before exercise, but similar post-exercise. After RE, monocyte counts were 2.4% (95%CI: 1.1 to 3.9%) higher in the PG. Lymphocyte levels in the PG were lower both before (DM: -13; IC95%: -6 to -20%) and after (DM: -8; IC95%: -1 to -14%) RE. Conclusions: Practitioners exhibit greater neutrophil and monocyte reactivity following an RE session, but demonstrate residual lymphopenia associated with regular training.