Metabolic Demands of Yoga at Varying Tempos and Compared With Walking.

BACKGROUND: Yoga is a popular alternative to walking, but the tempo at which asanas must be performed to elicit comparable metabolic and cardiorespiratory demands is unknown. Therefore, the authors aim to compare the metabolic demands of moderate-intensity walking to Surya Namaskar yoga performed at varying tempos. METHODS: Inactive obese adults with limited prior yoga experience (n = 10) completed 10 minutes of treadmill walking at a self-selected pace (rating of perceived exertion = 12-13) and three, 10-minute bouts of yoga at a low (6 s/pose; LSUN), medium (4 s/pose; MSUN), and high (3 s/pose; HSUN) tempo with 10-minutes rest between exercise bouts. RESULTS: Mean metabolic equivalents observed in MSUN (3.64 [0.607]), HSUN (4.22 [0.459]), and treadmill (5.29 [1.147]) were greater than 3.0 (P ≤ .01), but not LSUN (3.28 [0.529], P = .13). Treadmill elicited greater caloric and kilocaloric expenditure (1.36 [0.23] L·min-1; 64 [11] kcal) than LSUN (0.87 [0.24] L·min-1; 39 [11] kcal) and MSUN (1.00 [0.29] L·min-1; 45 [13] kcal) (P ≤ .01). Absolute V˙O2 between yoga tempos were not different, but relative V˙O2 was higher in HSUN (14.89 [1.74] mL·min-1·kg) versus LSUN (11.39 [1.83] mL·min-1·kg) (P = .02). CONCLUSIONS: Yoga can meet (LSUN) or exceed (MSUN and HSUN) moderate-intensity exercise recommendations. For unfit or obese populations, varying tempos of yoga practice may serve as a lower-impact option for beginning an exercise program.

Leukocytosis occurs in response to resistance exercise in men.

The purpose of this study was to determine the effects of a single bout of resistance exercise on immune cell numbers of moderately active men. Subjects were 16 male volunteers (mean +/- standard deviation [SD] age 30 +/- 7 years, height 180.1 +/- 7.0 cm, mass 83.97 +/- 10.33 kg); 8 were randomly assigned to treatment and 8 to control groups. Treatment was a common resistance training routine (3 sets of 8-10 repetitions at 75% of 1 repetition maximum) of 8 large muscle mass exercises using resistance machines. Blood samples were drawn before exercise and at 0 minutes (P0), 15 minutes (P15), and 30 minutes (P30) postexercise. Control subjects sat quietly in the training facility; blood was drawn at the same intervals as treatment. Leukocyte and lymphocyte (LY) subpopulation numbers were determined. Statistical analysis was analysis of variance (ANOVA) (repeated measures, p < or = 0.050) and multiple comparisons (Dunn method) to isolate variability. All leukocyte subpopulations, except basophils (BA) and eosinophils (EO), increased and counts declined by P15 and P30. Only neutrophils (NE) did not return to preexercise levels by P30. The majority of resistance exercise induced leukocytosis was due to an increase in circulating LY (natural killer cells increased most, CD4+/CD8+ ratio unchanged) and monocytes (MO). The transient, inconsequential immune cell population responses to resistance exercise are similar to those during aerobic activity. The lack of large alterations in and rapid recovery from cell number changes suggests that resistance exercise is not immunosuppressive.