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Previous research has shown significantly lower arterial distensibility (AD) after resistance exercise (RE) yet higher AD after aerobic exercise (AE). These changes may be related to exercise-induced differences in vasodilatory capacity. The purpose of this study was to investigate the vasodilatory and AD responses to acute AE and RE. Forearm blood flow (FBF) during reactive hyperemia (RH) was assessed before and 60 minutes after exercise, whereas aortic and femoral pulse wave velocity was measured as an index of arterial stiffness pre, 40, and 60 minutes after an acute bout of AE (30-minute leg ergometry at 650/0 of [[??]o.sub.2]peak) and RE (3 sets, 10 reps; upper and lower body at 65% 1 repetition maximum) in 10 male subjects (24.9 [+ or -] 0.86 years). Area under the curve (AUC) was employed to determine differences in flow. After the intervention, we found that central pulse wave velocity decreased 8% after AE and remained depressed at this level through 60 minutes of observation, whereas RE increased central pulse wave velocity 9.8% from pre to 40 and 60 minutes postexercise. Area under the curve for FBF-RH significantly increased 38% after RE, yet there was no significant change after AE. Forearm vasodilatory capacity increased after acute RE but not after acute AE. This suggests that changes in AD may be disassociated from changes in vasodilatory capacity after acute exercise. Further, in a direct comparison of RE vs. AE, we have shown that RE has greater increases in limb blood flow and augments postexercise hypotension greater at 40 minutes postexercise when compared to AE. KEY WORDS arterial stiffness, blood flow, resistance exercise, vasodilatory capacity, pulse wave velocity

African Americans have a greater prevalence of hypertension and diabetes compared with white Americans, and both autonomic dysregulation and inflammation have been implicated in the etiology of these disease states. The purpose of this study was to examine the cardiac autonomic and systemic inflammatory response to resistance training in young African-American and white men. Linear (time and frequency domain) and nonlinear (sample entropy) heart rate variability, baroreflex sensitivity, tonic and reflex vagal activity, and postexercise heart rate recovery were used to assess cardiac vagal modulation. C-reactive protein (CRP) and white blood cell count were used as inflammatory markers. Twenty two white and 19 African-American men completed 6 wk of resistance training followed by 4 wk of exercise detraining (Post 2). Sample entropy, tonic and reflex vagal activity, and heart rate recovery were increased in white and African-American men following resistance training (P < 0.05). Following detraining (Post 2), sample entropy, tonic and reflex vagal activity, and heart rate recovery returned to baseline values in white men but remained above baseline in African-American men. While there were no changes in white blood cell count or CRP in white men, these inflammatory markers decreased in African-American men following resistance training, with reductions being maintained following detraining (P < 0.05). In conclusion, resistance training improves cardiac autonomic function and reduces inflammation in African-American men, and these adaptations remained after the cessation of training. Resistance training may be an important lifestyle modification for improving cardiac autonomic health and reducing inflammation in young African-American men. heart rate variability; exercise; heart rate recovery; inflammation

Young African-American men have altered macrovascular and microvascular function. In this cross-sectional study, we tested the hypothesis that vascular dysfunction in young African-American men would contribute to greater central blood pressure (BP) compared with young white men. Fifty-five young (23 yr), healthy men (25 African-American and 30 white) underwent measures of vascular structure and function, including carotid artery intima-media thickness (IMT) and carotid artery [beta]-stiffness via ultrasonography, aortic pulse wave velocity, aortic augmentation index (AIx), and wave reflection travel time (Tr) via radial artery tonometery and a generalized transfer function, and microvascular vasodilatory capacity of forearm resistance arteries with strain-gauge plethysmography. African-American men had similar brachial systolic BP (SBP) but greater aortic SBP (P < 0.05) and carotid SBP (P < 0.05). African-American men also had greater carotid IMT, greater carotid [beta]-stiffness, greater aortic stiffness and AIx, reduced aortic Tr and reduced peak hyperemic, and total hyperemic forearm blood flow compared with white men (P < 0.05). In conclusion, young African-American men have greater central BP, despite comparable brachial BP, compared with young white men. Diffuse macrovascular and microvascular dysfunction manifesting as carotid hypertrophy, increased stiffness of central elastic arteries, heightened resistance artery constriction/blunted resistance artery dilation, and greater arterial wave reflection are present at a young age in apparently healthy African-American men, and conventional brachial BP measurement does not reflect this vascular burden. augmentation index; arterial stiffness

The purpose of this study was to examine heart rate recovery (HRR) and linear/nonlinear heart rate variability (HRV) before and after resistance training. Fourteen young men (25.0 [+ or -] 1.1 yr of age) completed a crossover design consisting of a 4-wk time-control period, 6 wk of resistance training (3 days/wk), and 4 wk of detraining. Linear HRV was spectrally decomposed using an autoregressive approach. Nonlinear dynamics of heart rate complexity included sample entropy (SampEn) and Lempel-Ziv entropy (LZEn). HRR was calculated from a graded maximal exercise test as maximal heart rate attained during the test minus heart rate at 1 rain after exercise (HRR). There was no change in SampEn, LZEn, or HRR after the time-control portion of the study (P > 0.05). SampEn (P < 0.05), LZEn (P < 0.05), and HRR (P < 0.05) increased after resistance training and returned to pretraining values after detraining. There was no change in spectral measures of HRV at any time point (P > 0.05). These findings suggest that resistance exercise training increases heart rate complexity and HRR after exercise but has no effect on spectral measures of HRV in young healthy men. These autonomic changes regress shortly after cessation of training. heart rate variability; entropy; parasympathetic; autonomic

Background. The purpose of this study was to determine the efficacy of 10 weeks of resistance (RT), functional (FF), or functional plus resistance (FRT) training in older adults who modify tasks of everyday life and are at risk for subsequent disability. Methods. Thirty-two older adults (75.8 [+ or -] 6.7 years) were tested following a control period and training. The primary outcome of the study was the number of task modifications and timed performance on eight tasks of daily life. Secondary outcomes included knee and elbow strength (extension and flexion), body composition, self-reported physical function, single-leg balance time, walking speed, and time to vacuum a carpet. The RT group performed progressive intensity training, and the FT group performed task-specific exercises 2 days per week. The FRT group performed 1 day of each training type. Results. No changes occurred in the control period. All three training groups reduced the need to modify tasks of everyday life (RT: 21%, FRT: 26%, and FT: 28%) and improved self-rated function and time to vacuum a carpet. Individuals who performed FT either 1 or 2 days per week also reduced their timed performance (RT: 2.5% [p = 0.48], FRT: 18.5%, and FT: 23%). Strength gains were primarily found in groups that perforated RT either 1 or 2 days per week (RT and FRT). No significant changes occurred in walking speed, single-leg balance, or body composition. Conclusion. The benefits of exercise are dependent on tasks performed during training. Exercise recommendations for low-functioning older adults should reflect task-specific exercise to prevent the onset of disability.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2007.02.035 Byline: Sae Young Jae (a), Mercedes R. Carnethon (b), Kevin S. Heffernan (a), Yoon-Ho Choi (c), Moon-Kyu Lee (c), Bo Fernhall (a) Abstract: Carotid atherosclerosis is a risk factor for cardiovascular mortality and may represent hypertension-related target organ damage. Cardiorespiratory fitness is inversely associated with cardiovascular mortality in hypertensive men. We tested the hypothesis that higher levels of cardiorespiratory fitness are inversely associated with the prevalence of carotid atherosclerosis in a cross-sectional study of 2532 (53.2 [+ or -] 8.5 years old) hypertensive men. Author Affiliation: (a) Department of Kinesiology and Community Health, University of Illinois, Urbana-Champaign, IL (b) Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL (c) Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, South Korea Article History: Received 20 November 2006; Accepted 22 February 2007

Functional magnetic resonance imaging (fMRI) is used to identify zone state patterns of neural activation that occurs among athletes during a hypnotically recalled zone-sate performance. The analysis of composite group data has revealed significant neural activation of zone performance (ZP) over normal performance (NP) thereby indicating that performance in a zone state involves identifiable characteristics of neural processing.