Purpose: To examine strength, range of motion, anthropometric, and physiological contributions to novice surface-combat-swimming (sCS) performance and establish differences from freestyle-swimming (FS) performance to further understand the transition of FS to sCS performance. Methods: A total of 13 competitive swimmers (7 male and 6 female; 27.7 [2.3] y; 176.2 [2.6] cm; 75.4 [3.9] kg) completed 8 testing sessions consisting of the following: physiological land-based measurements for maximal anaerobic and aerobic capacity and upper- and lower-extremity strength and range of motion, an sCS anaerobic capacity swim test measuring peak and mean force and fatigue index, 2 aerobic capacity tests measuring maximal aerobic capacity for both FS and sCS, and four 500-m performance swims for time, 1 FS, and 3 sCS. Separate multiple linear-regression analysis was used to analyze predictors of both sCS and FS performance models. Results: FS performance was predicted by the final FS maximal oxygen uptake with an R 2 of 42.03% (F 1,10 = 7.25; P = .0226), whereas sCS performance was predicted by isometric hip-extension peak strength with an R 2 of 41.46% (F 1,11 = 7.79; P = .0176). Conclusions: Results demonstrate that different physiological characteristics predict performance, suggesting that an altered strategy is used for novice sCS than FS. It is suggested that this may be due to the added constraints as mandated by mission requirements including boots, weighted gear, and clandestine requirements with hips lowered beneath the surface. Further research should examine the kinematics of the sCS flutter kick to improve performance by developing training strategies specific for the task.
Anne Z. Beethe, Elizabeth F. Nagle, Mita Lovalekar, Takashi Nagai, Bradley C. Nindl and Christopher Connaboy
Ethan Edward Hull, Dana L. Rofey, Robert J. Robertson, Elizabeth F. Nagle, Amy D. Otto and Deborah J. Aaron
Physical activity (PA) tends to decrease from adolescence to young adulthood, and factors that have been proposed to contribute to this decrease are life transitions. The focus of this study is to examine life transitions, such as marriage and parenthood, and the impact they may have on the physical activity levels of young adults.
This 2-year prospective analysis assessed physical activity (hrs/wk) and sociodemo-graphics in young adults (n = 638, 48% male, 15% nonwhite, 24 ± 1.1 years old) via questionnaire. PA data were normalized through log transformations and examined using ANCOVAs, controlling for appropriate covariates.
ANCOVA results showed that becoming married did not significantly change PA compared with individuals who stayed single [F(1,338) = 0.38, P = .54, d = 0.06]. Conversely, PA was significantly lower [F(1,517) = 6.7, P = .01, d = 0.41] after having a child, compared with individuals who stayed childless.
These results suggest that marriage does not impact PA in young adults, but having a child significantly decreases PA in parents, and may offer an optimal period of intervention.