IMMUNE-RESPONSE TO EXERCISE TRAINING AND OR ENERGY RESTRICTION IN OBESE WOMEN/

Purpose: The effect of exercise training (five 45-min walking sessions /wk at 60-75% maximum heart rate) and/or moderate energy restriction ( 4.19-5.44 MJ or 1,200-1,300 kcal.d(-1)) on innate and adaptive immunit y (including mitogen-stimulated lymphocyte proliferation (MSLP), natur al killer cell activity (NKCA), and monocyte and granulocyte phagocyto sis and oxidative burst (MGPOB) was studied in obese women (N = 91, ag e 45.6 +/- 1.1 yr, body mass index 33.1 +/- 0.6 kg m(-2)) randomized t o one of four groups: control (C), exercise (E), diet (D), exercise, a nd diet (ED). Methods: Aerobic power, body composition, and immune fun ction were measured in all subjects before and after a 12-wk diet inte rvention period, with data analyzed using a 4 x 2 repeated measures de sign. All subjects self-reported symptoms of sickness in health logs u sing a preceded checklist. Statistical significance was set at P less than or equal to 0.05. Results: Data from this study indicate that alt hough exercise training was unrelated to any significant changes in re sting immune function, the number of days with symptoms of upper respi ratory tract infection (URTI) was reduced relative to subjects in the nonexercise groups (5.6 +/- 0.9 and 9.4 +/- 1.1 sickness days, respect ively, P < 0.05). Energy restriction and weight loss (7.9 +/- 0.7 kg) was associated with a significant decrease in MSLP, but no change in N KCA, MGPOB, or URTI. Conclusion: The data are consistent the viewpoint that weight loss, even at a moderate rate, is associated with a decre ase in mitogen-stimulated lymphocyte proliferation without a change in various measures of innate immunity of the blood compartment.