The factors that best account for differences in strength across all types of exercise, body types, and training histories are not well understood. The purpose of this study was to assess the effects of strength level and body composition on upper- and lower-body work capacity in adult men. From a cohort of 295 adult men (25.6 ± 7.5 years, 178 ± 8 cm, 85.2 ± 15 kg), low-strength (LS, n = 72) and high-strength (HS, n = 66) samples were selected based on 1 repetition maximum (1RM) bench press (BP) and leg strength (LP) values. Work capacity for each exercise was determined from the product of repetition weight (80% 1RM) and maximum repetitions-to-fatigue (RTF). Body composition was measured using dual-energy x-ray absorptiometry. The HS group was significantly greater than the LS group in total body mass and fat-free mass but not in age, height, fat mass, or %fat. Low-strength and HS groups were not significantly different (p > 0.05) in RTF for either BP (8.7 ± 3.1 vs. 8.3 ± 1.9 reps, respectively) or LP (15.6 ± 7.6 vs. 17.0 ± 6.3 reps, respectively), making the ratio of RTF for BP vs. LP nonsignificant (LS = 2.0 ± 1.0; HS = 2.2 ± 0.9). The HS group produced significantly greater (p < 0.001) absolute and relative work capacities for both BP and LP compared with the LS group. Repetitions-to-fatigue had a greater influence on BP (r2 = 0.74) and LP (r2 = 0.85) work capacities in the LS group than did RepWt (r2 = 0.07 and 0.28, respectively). In the HS group, RTF (r2 = 0.79) had a greater influence than RepWt (r2 = 0.10) on BP work capacity, whereas the 2 components were more similar for LP work capacity (r2 = 0.64 and 0.47, respectively). When evaluated at the same %1RM, muscular endurance is similar across divergent strength levels meaning that work capacity (load × reps) will be greater for HS individuals. Controlling for the influence of body composition variables (e.g., fat or fat-free mass) does not eliminate the difference in work capacity between strength groups suggesting that other factors are accounting for strength expression. Prescribing repetitions against a fixed relative load is largely dependent on exercise type and must be considered by strength and conditioning professionals.

CONTEXT Recently, studies using a social ecological perspective have identified important micro- and macro-level risk factors for excessive adiposity in youth. Although considerable research exists examining these relationships, few studies have applied a socioecological approach to simultaneously examine both micro- and macro-level factors in young children while objectively assessing adiposity via dual-energy x-ray absorptiometry (DXA). OBJECTIVE To examine race and sex differences in adiposity measured by DXA in a large sample of young children and to identify both micro- and macro-level correlates of adiposity. DESIGN Cross-sectional. SETTING AND PARTICIPANTS Elementary school children (N = 495) from the southeastern United States participated. Anthropometrics, percentage body fat via DXA, and psychosocial variables via questionnaire were assessed in the Fall of 2003. Community-level sociodemographic data and built-environment variables via geographic information system were collected in Spring 2009. Data analyses were completed in the Spring of 2010. RESULTS Percentage body fat in white children was higher than in nonwhite children. Higher percentage body fat and poorer cardiovascular fitness were found in females compared with males. Percentage body fat was higher in children who had lower athletic competence and lived in neighborhoods with higher percentages of minority residents. CONCLUSION This study provides preliminary support for the social-ecological model to explain variance in adiposity in children. Developers of health promotion programs for children living in minority neighborhoods should consider factors at multiple levels of the ecological model when designing and implementing programs.

Objective. This exploratory cross-sectional study examined nurse practitioners' (NPs) and physician assistants' (PAs) perceptions about their physical activity counseling practices.Method. Participants were currently practicing NPs (n =240) and PM (n = 78) primarily in Arizona. USA during 2010. Participants completed a modified version of the Promotion of Physical Activity by Nurse Practitioners Questionnaire either online or in person during a practitioner specific conference. Mann-Whitney U tests and Chi-Square analyses examined differences between NPs and PAs.Results. NP respondents were older (48 vs. 40 yrs, p<0.001) and more likely to be female (94% vs. 76%; p<0.001) compared to PAs. The majority of respondents (NP5:75%; PA5:64%; p < 0.07) reported routinely counseling patients about physical activity. There were no differences in perceived knowledge (p = 0.10) or confidence (p = 0.75) to provide physical activity counseling between NPs and PAs. Approximately half of all respondents reported receiving training to provide physical activity counseling as part of their educational preparation to become a health practitioner (p = 0.18).Conclusion. Study results indicate that NPs and PAs are knowledgeable, confident and currently providing some level of physical activity counseling to patients. However, the majority of respondents are interested in receiving additional training to aid in providing physical activity counseling. (C) 2012 Elsevier Inc. All rights reserved.

Heavy resistance training may enhance low-intensity work capacity (load x repetitions) but reduce high-intensity work capacity in both competitive and recreational individuals. However, most research has focused on upper-body work capacity with little information available for lower-body work capacity. PURPOSE: The purpose of this study was to assess the effects of strength level and body composition on upper- and lower-body work capacity in adult men. METHODS: From 295 adult men, low-strength (LS, n = 72) and high-strength (HS, n = 66) samples were selected based on one-repetition maximum (1RM) bench press (BP) and leg strength (LP). Group limits were determined using the lower and upper 40% of the sample. Work capacity was determined from repetition weight (RepWt = 79.5 ± 2.5% of 1RM) multiplied by maximum repetitions-to-fatigue (RTF). Body composition was measured using DXA. RESULTS: HS group was significantly greater in body mass and lean mass than LS, but not different in age, height, fat mass, or %fat. LS and HS groups were not significantly different in the RTF for either BP (8.7 ± 3.1 vs 8.3 ± 1.9) or LP (15.6 ± 7.6 vs 17.0 ± 6.3), which made the ratio of LP-RTF to BP-RTF nonsignificantly different between the LS (2.0 ± 1.0) and HS (2.2 ± 0.9) groups. RTF in the BP and LP were significantly correlated in the LS group (r = 0.31) but not in the HS group (r = 0.11). Significantly greater RepWt in the HS group resulted in greater (p<0.001) absolute and relative work capacities for both BP (818 ± 207 and 9.1 ± 2.6) and LP (4,354 ± 2,086 and 48.4 ± 23.2) vs. the LS group (522 ± 183 and 6.8 ± 2.3; 1,856 ± 1,029 and 24.2 ± 13.9). RTF explained a larger percent contribution explaining BP and LP work capacities in the LS group (79% and 85%, respectively) than did RepWt (21% and 15%, respectively). In the HS group, RTF (81%) contributed more than RepWt (19%) to explaining BP work capacity, while the two components were more similar in explaining LP work capacity (60% and 40%, respectively). CONCLUSION: When work is determined using the same %1RM load, LS and HS individuals produce equivalent muscular endurance values when evaluated by RTF, but HS individuals have greater work capacity when the criterion is determined as load × RTF. Controlling for body composition among strength groups does not eliminate the difference in work capacity.

AbstractObjectiveTo assess the dietary quality of older women with and without rheumatoid arthritis (RA) using the Healthy Eating Index-2005 (HEI-2005) to identify potential strategies to improve the nutritional status.DesignCross-sectional. Diet was assessed using 7 d food records and analysed for nutrient composition (Food Processor v. 7·11). Diet quality was determined using the HEI-2005, a measure of compliance with 2005 US Dietary Guidelines. Individuals with RA completed a self-reported evaluation of arthritis (pain scale and disability index). Independent two-tailedttests or Mann–Whitney tests compared the differences between groups and correlations were computed between HEI-2005 and measures of disease reactivity.SettingArizona, USA.SubjectsOlder (≥ 55 years) women (n108) with RA (n52) and healthy controls (HC;n56).ResultsThere were no differences between groups in age, weight, or BMI (kg/m2). HC participants had higher mean HEI-2005 scores for whole fruit (cups;P= 0·02), total fruit (cups;P= 0·05), whole grains (oz;P= 0·004), oil (g;P= 0·05) and total HEI score (P= 0·04) than the RA group. In the RA group, these same HEI components were inversely correlated with disability index (r= −0·20,P= 0·04). Participants with RA reported lower mean intakes of carbohydrate (g;P= 0·02), fibre (g;P= 0·01) and vitamin C (mg;P= 0·04).ConclusionsThis is the first study examining the dietary quality in older women with and without RA using the HEI-2005. Living with RA was associated with significantly lower dietary quality. Since even small changes in dietary quality can translate into better nutritional status, future interventions should focus on increasing dietary quality in this high-risk group.

BACKGROUND:This study tested the effectiveness of a stair use promotion strategy in visible and hidden stairwells during intervention and post intervention follow up.METHODS:A quasi-experimental study design was used with a 1 week baseline, a 3 week intervention, and post intervention at 2 and 4 weeks in 4 university buildings in San Antonio, Texas with stairwells varying in visibility. Participants were students, faculty, staff, and visitors to the 4 buildings. A total of 8431 observations were made. The intervention incorporated motivational signs with direction to nearby stairwells placed by elevators to promote stair use. Stair and elevator use was directly observed and recorded. Logistic regression analyses were used to test whether stair versus elevator use varied by intervention phase and stairwell visibility.RESULTS:Stair use increased significantly (12% units) during the intervention period and remained above baseline levels during post intervention follow-up. At baseline, visible stairs were 4 times more likely to be used than hidden stairs; however, the increase in stair use during intervention was similar in both types of stairwells.CONCLUSIONS:Motivational and directional signage can significantly increase stair use on a university campus. Furthermore, stairwell visibility is an important aspect of stair use promotion.

Objective To determine the safety and efficacy of altering the ratio of carbohydrate and protein in low-energy diets in conjunction with a popular exercise program in obese women. Design Matched, prospective clinical intervention study to assess efficacy of varying ratios of carbohydrate and protein intake in conjunction with a regular exercise program. Participants One-hundred sixty one sedentary, obese, pre-menopausal women (38.5 ± 8.5 yrs, 164.2 ± 6.7 cm, 94.2 ± 18.8 kg, 34.9 ± 6.4 kg·m -2 , 43.8 ± 4.2%) participated in this study. Participants were weight stable and not participating in additional weight loss programs. Methods Participants were assigned to either a no exercise + no diet control (CON), a no diet + exercise group (ND), or one of four diet + exercise groups (presented as kcals; % carbohydrate: protein: fat): 1) a high energy, high carbohydrate, low protein diet (HED) [2,600; 55:15:30%], 2) a very low carbohydrate, high protein diet (VLCHP) [1,200 kcals; 63:7:30%], 3) a low carbohydrate, moderate protein diet (LCMP) [1,200 kcals; 50:20:30%] and 4) a high carbohydrate, low protein diet (HCLP) [1,200 kcals; 55:15:30%]. Participants in exercise groups (all but CON) performed a pneumatic resistance-based, circuit training program under supervision three times per week. Measurements Anthropometric, body composition, resting energy expenditure (REE), fasting blood samples and muscular fitness assessments were examined at baseline and weeks 2, 10 and 14. Results All groups except CON experienced significant reductions ( P < 0.05 – 0.001) in waist circumference over 14 weeks. VLCHP, LCHP and LPHC participants experienced similar but significant ( P < 0.05 – 0.001) reductions in body mass when compared to other groups. Delta responses indicated that fat loss after 14 weeks was significantly greatest in VLCHP (95% CI: -5.2, -3.2 kg), LCMP (-4.0, -1.9 kg) and HCLP (-3.8, -2.1 kg) when compared to other groups. Subsequent reductions in % body fat were significantly greater in VLCHP, LCMP and HCLP participants. Initial dieting decreased ( P < 0.05) relative REE similarly in all groups. All exercise groups significantly ( P < 0.05) improved in muscular fitness, but these improvements were not different among groups. Favorable but non-significant mean changes occurred in lipid panels, glucose and HOMA-IR. Leptin levels decreased ( P < 0.05) in all groups, except for CON, after two weeks of dieting and remained lower throughout the 14 week program. Exercise participation resulted in significant improvements in quality of life and body image. Conclusion Exercise alone (ND) appears to have minimal impact on measured outcomes with positive outcomes apparent when exercise is combined with a hypoenergetic diet. Greater improvements in waist circumference and body composition occurred when carbohydrate is replaced in the diet with protein. Weight loss in all diet groups (VLCHP, LCMP and HCLP) was primarily fat and stimulated improvements in markers of cardiovascular disease risk, body composition, energy expenditure and psychosocial parameters.

Limited evidence exists showing the associations of abdominal obesity and cardiorespiratory fitness with inflammatory markers in a large US adolescent population. PURPOSE: We investigated whether abdominal obesity or cardiorespiratory fitness relates to inflammatory markers in 4,800 healthy U.S. adolescents, aged 12 to 17 years, from the National Health and Nutrition Examination Survey (1999-2004). METHODS: Body height was measured with a stadiometer, and weight was measured with a self-zeroing scale. Waist girth was measured at the midpoint between the bottom of the rib cage and above the top of the iliac crest. Abdominal obesity was classified as a waist girth greater than 90th percentile for age and sex. Cardiorespiratory fitness was measured by a submaximal exercise test, and classified as low, moderate, and high fitness categories. C-reactive protein was measured by latex-enhanced nephelometry, and white blood cell (WBC) count was measured by Beckman coulter method. Age-, sex-, and race-adjusted partial Pearson correlations were used to examine the relations of waist girth and CRF with inflammatory markers (CRP, WBC). General linear models were used to test mean differences for CRP and WBC across abdominal obesity and CRF categories. RESULTS: Abdominal obesity measured by waist girth was directly associated with CRP (r = 0.48, p<0.001) and WBC (r = 0.25, p<0.001) values in US adolescents. In contrast, cardiorespiratory fitness was inversely associated with CRP (r = −0.17, p<0.001) and WBC (r = −0.11, p<0.001) values. Furthermore, adolescents with abdominal obese had greater mean CRP values (p<0.001) and WBC values (p<0.001), respectively, as compared with their counterparts. We also observed that highly fit adolescents had lower mean CRP values (p<0.001) and WBC values (p<0.001), respectively, when compared with moderately and low fit adolescents. CONCLUSIONS: Abdominal obesity is directly associated with inflammatory markers in US adolescents. However, higher levels of cardiorespiratory fitness are inversely associated with inflammatory markers in young age groups.

The American College of Sports Medicine recommends regular participation in moderate to vigorous physical activity for all adults. However, the majority of the population does not meet these recommendations. Stair use is one recommended method of accumulating regular moderate physical activity. PURPOSE: To determine the effectiveness of a stair use promotion strategy in visible and hidden stairwells on a university campus. METHODS: Motivational and directional signs were placed near elevators in four university buildings for a three-week intervention. Observations (n=8,433) were made of stair and elevator use for one week prior, during the intervention and at two and four weeks post intervention. Logistic regression analyses were used to test whether stair versus elevator use varied by intervention phase and stairwell visibility. RESULTS: Stair use increased significantly (12% from 35.5% baseline) during the intervention period (OR 1.65, 95% CI 1.47-1.85; p < .001) and remained elevated at week two (OR 1.37, 95% CI 1.19-1.59) and week four (OR 1.75, 95% CI 1.51-2.03) after the intervention signs were removed, at 7.6% and 13.4% respectively. The increase in stair use during the intervention was similar in hidden and visible stairwells. During all phases of the study, participants were more likely to use visible stairs (OR 4.68, 95% CI 4.19-5.21). However, the interaction between visibility and study phases was not significant (χ2(1) = 1.26, p = 0.74), suggesting a comparable increase in use of hidden and visible stairwells at each study phase. CONCLUSIONS: Motivational and directional signage can significantly increase stair use on a university campus. Furthermore, stairwell visibility is an important aspect of stair use promotion.

Whether childhood obesity relates to inflammatory markers remains less explored. PURPOSE: We examined the relations of waist girth, body mass index, and body fatness to inflammatory markers (C-reactive protein and white blood cell count) in 2,745 healthy US children, aged 6 to 11 years, from the National Health and Nutrition Examination Survey (1999-2004). METHODS: Body weight and height were measured with a stadiometer and a self- zeroing scale, and body mass index (BMI: in kg/m2) was calculated. Age- and sex- specific overweight (≥95th percentile) and risk for overweight (85-<95th percentile) categories were classified by following the Centers for Disease Control and Prevention definitions. Percent body fat was estimated from the sum of triceps and subscapular skinfold thicknesses, and obesity was defined as over 25% body fat in boys and over 32% body fat in girls. Waist girth was measured with a steel measuring tape, and abdominal obesity was defined as a waist girth greater than 90th percentile for age and sex. C-reactive protein (CRP) was measured by latex-enhanced nephelometry, and white blood cell (WBC) count was measured by Beckman coulter method. Partial Pearson correlations were used to examine the relations of waist girth, BMI, and body fatness with inflammatory markers (CRP, WBC) after adjustment for age, sex, and race. General linear models were used to test mean differences for CRP and WBC across abdominal obesity (yes/no), overweight (yes/no), and obesity (yes/no) categories after adjustment for covariates. RESULTS: Partial Pearson correlations documented that there were significant associations between CRP with waist girth (r = 0.45, p<0.001), BMI (r = 0.46, p<0.001), and body fatness (r = 0.48, p<0.001), and between WBC with waist girth (r = 0.17, p<0.001), BMI (r = 0.16, p<0.001), and body fatness (r = 0.20, p<0.001). We also observed that obese (p<0.001), overweight (p<0.001), or abdominal obese (p<0.001) children had greater mean CRP values and WBC values, respectively, as compared with their counterparts. CONCLUSION: Childhood obesity is directly associated with inflammatory markers in US children. Continued efforts are needed to reduce childhood obesity and to increase physical activity in US children.

PURPOSE: To identify micro- (physiological, behavioral & psychosocial) and macro-level (socioeconomic, cultural & environmental) risk factors related to adiposity in children. METHODS: Subjects were 600 3rd graders (mean age 8.5 y; 46% white) in 17 urban and rural elementary schools in Southeast US. Micro-level risk factors included age, sex, race, number of physical activity facilities within 0.5 and 3.0 mi of subjects' homes (GIS mapping), cardiovascular fitness (CVF: step test), subjects' eligibility for free/reduced lunch, global self-worth, athletic competence and physical appearance competence. Macro-level risk factors included %students eligible for free/reduced school lunch and %minority students in each school, neighborhood street connectivity, population density, %minority population, %rural residency and economic deprivation. Neighborhood was denned by school boundaries. Percent body fat (%BF) was obtained by dual-energy x-ray absorptiometry). Mixed model analysis of variance was used for data analysis of the children within schools using a two-level school effects model. RESULTS: The intra-class correlation of schools for %BF was 0.065. Significant between-school variance was accounted for by %minority students (39%) and population density (35%). The base model (age, race & sex) accounted for 8% of the within-school variance; higher %BF was related to being white and female. Additional within-school variance was accounted for by CVF (27%), athletic competence (1 %) and global self-worth (1%). The final model (age, race, sex, CVF, athletic competence & %minority students) accounted for 53% of between-school variance and 35% of within-school variance in %BF. Higher %BF was related to lower CVF, poorer athletic competence and lower %minority students in schools. CONCLUSIONS: This study suggests that high adiposity levels were related to attending schools with a high percentage of non-minority students, which is noteworthy. Supported by NIH DK63391.

Dual Energy X-ray Absorptiometry (DEXA) has gained popularity as a valid measure of human body composition. A distinct advantage of this method is its ability to partition/section the body into regions for analysis. While much information has been reported in regards to body composition changes in overweight or sedentary populations, little information has been reported concerning the regional fat and lean composition of the human body of active males across the age span. PURPOSE: To assess the absolute and relative amounts of bone, fat and lean tissue in men across three age groups. METHODS: Moderately active and apparently healthy men (26.9±8.2y, 178.1±7.31cm, 84.2±14.5kg, 17.3±6.6% fat, n=334) had whole-body body composition scans completed using a Hologic QDR-4500W DEXA (version 9.80C). Participants were required to have been weight training on their entire body for a minimum of 6 months at least 3 days per week. All subjects were divided into three age cohorts (Y1: <25y, Y2:26–35y, and O:36–50y) and reported as M±SD, respectively. RESULTS: Multivariate ANO VA revealed no significant difference in height among all three groups and no difference in weight for Y1 (80.7±12.7kg) and Y2 (86.9±14.6kg). No differences in total bone mineral density were found for any age group. The O group had significantly greater body mass (p < 0.05) as well as absolute fat content on the upper body (right arm + left arm + trunk fat) (Y1:7.3±3.9, O:12.3±6.9kg, p < 0.05) and both legs (Y1:4.9±2.6, O:5.9±2.6 kg, p < 0.05) compared to Y1. Groups Y1 and Y2 were not significantly different in fat content of the legs but Y2 had significantly more trunk fat than Y1 (Y1: 6.1±7.5kg and Y2:9.1±13.7kg, p < .0.05). All groups were similar in lean tissue mass of the extremities, but Y1 had significantly less trunk lean tissue mass than the other two groups (Y1:30. 2±5.5, Y2:31.9±7.9, O:32.9±9.4 kg, p < 0.05). Comparing these tissues produced higher fat-to-lean ratios for the older group for the arms and trunk not for legs. CONCLUSIONS: The greater fat content of older men appears to be due to accumulation on the arms and trunk but not on the legs. It appears that pronounced changes in body composition distribution occur during 26–35 years of age in recreationally resistance-trained males. The pattern of adipose and lean tissue distribution throughout the age span appears to occur irrespective of their resistance training background in comparison to previous findings.