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Aim: Assess the effect of low‐ and high‐volume blood flow restriction training (BFR) on maximal aerobic capacity (VO2max) and determine if alteration in VO2max is mediated through changes in hemoglobin mass (Hbmass) and blood volume. Methods: Participants' Hbmass (CO‐rebreathe), single, and double‐leg VO2max and blood volume regulating hormonal responses (renin and copeptin) were measured before and after BFR training. Training consisted of treadmill walking either (1) twice‐daily for 4week (CON and BFRHV) or (2) twice‐weekly for 6week (BFRLV). Each session consisted of five intervals (3 min, 5% incline, 5 km/h, 100% of lowest occlusion pressure), with 1 min of standing rest between sets. Results: VO2max increased using both training exposures, in as quickly as 2‐weeks (BFRLV baseline to 4week: +315 ± 241 mL (8.7%), p = 0.02; BFRHV baseline to 2week: +360 ± 261 mL (7.9%), p < 0.01), for the BFRLV and BFRHV groups, with no change in CON. Single‐ and double‐leg VO2max improved proportionately (single/double‐leg VO2max ratio: BFRLV 78 ± 4.9–78 ± 5.8%, BFRHV 79 ± 6.5–77 ± 6.5%), suggesting that the mechanism for increased VO2max is not solely limited to central or peripheral adaptations. Hbmass remained unchanged across groups (CON: +10.2 ± 34 g, BFRLV: +6.6 ± 42 g, BFRHV: +3.2 ± 44 g; p = 0.9), despite a significant release of blood volume regulating hormones after initial BFR exposure (renin +20.8 ± 21.9 ng/L, p < 0.01; copeptin +22.0 ± 23.8 pmol/L, p < 0.01), which was blunted following BFRHV training (renin: +13.4 ± 12.4 ng/L, p = 0.09; copeptin: +1.9 ± 1.7 pmol/L, p = 0.98). Conclusion: BFR treadmill walking increases VO2max irrespective of changes in Hbmass or blood volume despite a large release of blood volume regulating hormones in response to BFR treadmill walking. [ABSTRACT FROM AUTHOR]

Objective: This study had four objectives: 1) to examine the association between sexual victimization and weight regulation across three samples of adolescent girls, 2) to assess whether sexual victimization is associated with more extreme forms of weight regulation in girls, 3) to discern whether sexual victimization has implications for the use of multiple forms of weight regulation, and 4) to address the role of physical victimization in explaining these relationships. Method: Data from three separate samples of 9th-12th graders were used to test these hypotheses. Girls from the upper Midwest responded to survey questions related to victimization and weight regulation in a largely urban sample (N = 2,086), a rural sample (N = 2,629), and a statewide sample (N = 966). Results: Logistic regression revealed that sexual victimization was consistently associated with weight regulation in adolescent girls, independent of the effects of physical victimization. In the urban sample, being sexually victimized was associated with an increase in the probability of purging by 18% relative to not being sexually victimized. Sexual victimization was associated more strongly with extreme forms of weight regulation and significantly discriminated whether girls would choose multiple weight regulation forms. Conclusions: Sexual victimization contributes unique variance to the probability that girls will practice weight regulation techniques. Data from three independent samples confirms that being violated sexually places girls at risk for various health compromising eating behaviors. [C] 2001 Elsevier Science Ltd. All fights reserved. Keywords: Sexual victimization; Weight regulation; Physical victimization.