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These findings demonstrate the potential beneficial impact of meditation on blood pressure and heart rate in the natural environment in healthy normotensive youth.

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The purpose of this study was to determine whether a 4-week isotonic resistance training program using Theraband elastic tubing and lightweight dumbbells would significantly increase concentric shoulder rotator strength or velocity of serve or both in a group of elite-level tennis players. Twenty-two male and female varsity college tennis players were randomly assigned to control or 4-week training groups. Subjects were pre- and posttested in concentric internal and external rotation torque using an isokinetic dynamometer. Functional performance was assessed before and after training by recording the peak and average velocities of eight maximal serves. The experimental group exhibited significant gains in internal rotation torque at both slow (120 deg/sec) and fast speeds (300 deg/sec) for total work and in peak torque to body weight ratio and torque acceleration energy at the fast speed. This group also exhibited significant gains in external rotation torque for the same parameters at fast speed. Regarding speed to serve, the experimental group exhibited significantly greater increase in peak speed (+6.0% compared with -1.8%) and average speed (+7.9% compared with -2.3%) compared with the control group. Men exhibited greater internal and external rotation torque on all parameters and in peak and mean speed of serve on both evaluations. Men also exhibited greater imbalance in external to internal rotation torque ratios. In conclusion, resistance training using Theraband tubing and lightweight dumbbells may have beneficial effects on strength and functional performance in college-level tennis players.

Abstract-Blacks exhibit greater vasoconstriction-mediated blood pressure (BP) increases in response to stress than do whites. Endothelin-1 (ET-1), a potent vasoconstrictive peptide, has been proposed as having a role in racial differences in stress reactivity. We evaluated the hemodynamic and plasma ET-1 levels of 41 (23 whites, 18 blacks, mean age 18.6 years) normotensive adolescent males at rest and in response to a video game challenge and forehead cold stimulation.Measurements were performed at catheter insertion and before and immediately after the 2 stressors, which were separated by 20-minute rest periods. Blacks exhibited higher absolute levels of diastolic blood pressure, total peripheral resistance index, or both in response to catheter insertion and to the video game challenge and during recovery from video game challenge and cold stimulation (PϽ0.05 for all). Blacks exhibited higher absolute levels of ET-1 at every evaluation point (PϽ0.05 for all) and greater increases in ET-1 in response to both stressors (psϽ0.05). These findings suggest that altered endothelial function may be involved in racial differences in hemodynamic reactivity to stress and possibly in the development of essential hypertension. Key Words: endothelin Ⅲ stress Ⅲ blood pressure Ⅲ race Ⅲ young adults Ⅲ blacks Ⅲ hypertension, essential B lacks experience a higher prevalence and earlier onset of essential hypertension (EH) and more frequent associated target-organ damage than do whites. 1 Although a few race-specific genetic factors have been identified, 2,3 raceshared physiological mechanisms that contribute to the development of EH (eg, increased sympathetic nervous system [SNS] arousal in response to stress) are believed to be differentially activated within different environmental contexts. It has been postulated that blacks experience greater chronic SNS arousal due to more frequent exposure to social and environmental stressors (eg, aversive social interactions related to socioeconomic status inequality, racism). 4 Although not entirely consistent, exaggerated blood pressure (BP) reactivity to brief laboratory stressors has been shown to be an independent predictor of future BP levels in youths and of EH in adults (see reviews 5-7 ). Studies that involve normotensive adults 8,9 and youths 10,11 have found that blacks exhibit greater BP increases in response to acute stress than do whites and that these differences are frequently mediated by greater increases in total peripheral resistance (TPR).The underlying physiological mechanisms responsible for enhanced vasoconstrictive responsivity (ie, increased TPR) to stress in blacks are unknown. Endothelial cell-derived vasoconstrictive and vasodilator substances are central to the regulation of vascular tone. Endothelin-1 (ET-1) is a 21-residue peptide with potent vasoconstrictive activity. 12 ET-1 is expressed by endothelial cells and is primarily released basolaterally to elicit smooth muscle cell contractions. 13 Therefore, circulating ET-1 may reflect only a minor portion o...