Joseph L. Andreacci

Concurrent validation of the OMNI perceived exertion scale for resistance exercise.

UNLABELLED The criterion variables were total weight lifted (Wttot ) determined separately for women and men during BC and KE, and blood lactic acid concentration ([Hla]) determined for a combined female ( N = 10) and male ( N = 10) subset during BC. Subjects performed three separate sets of 4, 8, and 12 repetitions for BC and KE at 65% one-repetition maximum. Rating of perceived exertion for the active muscles (RPE-AM) was measured during the mid and final repetition and RPE for the overall body (RPE-O) during the final repetition. : For both female and male groups across the three sets: (a) RPE-AM ranged from 3.6 to 8.2 for BC and 5.1 to 9.6 for KE and (b) RPE-O ranged from 2.4 to 6.7 for BC and 4.2 to 7.6 for KE. Positive linear regressions ranged from r = 0.79 to 0.91 ( P < 0.01) between Wttot and RPE-AM (mid), RPE-AM (final), and RPE-O for both BC and KE in both sex groupings. A positive ( P < 0.01) linear regression was found between [Hla] and RPE-AM (final) (r = 0.87) during BC. RPE did not differ between women and men at any measurement point within each set for BC and KE. RPE-AM (final) was greater ( P < 0.01) than RPE-O in the three sets of BC and KE. CONCLUSION Findings provided concurrent validation of the OMNI-RES to measure RPE for the active muscle and overall body in young recreationally trained female and male weight lifters performing upper- and lower-body resistance exercise.

Lipid and lipoprotein profiles, cardiovascular fitness, body composition, and diet during and after resistance, aerobic and combination training in young women

Abstract The purpose of this study was to evaluate the effects of various modes of training on the time-course of changes in lipoprotein-lipid profiles in the blood, cardiovascular fitness, and body composition after 16 weeks of training and 6 weeks of detraining in young women. A group of 48 sedentary but healthy women [mean age 20.4 (SD 1) years] were matched and randomly placed into a control group (CG, n=12), an aerobic training group (ATG, n=12), a resistance training group (RTG, n=12), or a cross-training group that combined both aerobic and resistance training (XTG, n=12). The ATG, RTG and XTG trained for 16 weeks and were monitored for changes in blood concentrations of lipoprotein-lipids, cardiovascular fitness, body composition, and dietary composition throughout a 16 week period of training and 6 weeks of detraining. The ATG significantly reduced blood concentrations of triglycerides (TRI) (P < 0.05) and significantly increased blood concentrations of high-density lipoprotein-cholesterol (HDL-C) after 16 weeks of training. The correlation between percentage fat and HDL-C was 0.63 (P < 0.05), which explained 40% of the variation in HDL-C, while the correlation between maximal oxygen uptake (V˙O2max) and HDL-C was 0.48 (P < 0.05), which explained 23% of the variation in HDL-C. The ATG increased V˙O2max by 25% (P < 0.001) and decreased percentage body fat by 13% (P < 0.05) after 16 weeks. Each of the alterations in the ATG had disappeared after the 6 week detraining period. The concentration of total cholesterol (TC), TRI, HDL-C and low density lipoprotein-cholesterol in the blood did not change during the study in RTG, XTG and CG. The RTG increased upper and lower body strength by 29% (P < 0.001) and 38%, respectively. The 6 week detraining strength values obtained in RTG were significantly greater than those obtained at baseline. The XTG increased upper and lower body strength by 19% (P < 0.01) and 25% (P < 0.001), respectively. The 6 week detraining strength values obtained in XTG were significantly greater than those obtained at baseline. The RTG, XTG and CG did not demonstrate any significant changes in either V˙O2max, or body composition during the training and detraining periods. The results of this study suggest that aerobic-type exercise improves lipoprotein-lipid profiles, cardiorespiratory fitness and body composition in healthy, young women, while resistance training significantly improved upper and lower body strength only.

Validation of the adult OMNI Scale of Perceived Exertion for Cycle Ergometer exercise

PURPOSE Concurrent and construct validity of the OMNI-Cycle Scale of Perceived Exertion were examined using young adult women and men (18-32 yr). METHODS Concurrent validity was established by correlating OMNI-Cycle Scale ratings of perceived exertion (RPE) with oxygen consumption (.VO2) and heart rate (HR) responses to a load-incremented cycle ergometer protocol. Construct validity was established by correlating RPE derived from the OMNI-Cycle Scale with RPE from the Borg (6-20) Scale. RPE, .VO2, and HR were measured during each exercise stage. RESULTS The range of exercise responses across the incremental test for the female and male groups was .VO2 = 0.92-2.74 L.min-1, HR = 107.2-167.2 beats.min-1, and OMNI Scale RPE-Overall, RPE-Legs, and RPE-Chest 1.0-9.1. Correlation/regression analyses indicated that RPE-Overall, RPE-Legs, and RPE-Chest distributed as a positive linear function of both .VO2 and HR (r = 0.81 to 0.95; P < 0.01). Undifferentiated and differentiated RPE-OMNI Scale distributed as a positive linear function of RPE-Borg Scale (r = 0.92 to 0.97; P < 0.01). ANOVA indicated that OMNI-Cycle RPE-Legs was higher (P < 0.01) than RPE-Chest at each exercise stage for both genders. CONCLUSION Concurrent and construct evidence supports use of the OMNI Scale by adult women and men to estimate RPE during cycle exercise.

The effects of frequency of encouragement on performance during maximal exercise testing

The aim of this study was to determine the effects of frequency of verbal encouragement during maximal exercise testing. Twenty-eight participants (12 males, 16 females) aged 20.9 - 1.5 years (mean - s ) performed a maximal exercise test ( V O 2max ) on a treadmill without any verbal encouragement. The participants were matched according to their pre-test V O 2max and placed into either a control group or one of three experimental groups. They performed a second exercise test (post-test) 1 week later. During the second test, the control group received no verbal encouragement; the 20 s (20E), 60 s (60E) and 180 s (180E) encouragement groups received verbal encouragement every 20, 60 and 180 s, respectively, beginning with stage 3 of the exercise test. Relative V O 2max , exercise time, blood lactate concentration, respiratory exchange ratio (RER) and ratings of perceived exertion (RPE) were not significantly different from the first test to the second test for the control group without verbal encouragement and the 180E group that received infrequent encouragement. Post-test values were significantly higher than pre-test values for the 20E and 60E groups. The post-test values of the 20E group were significantly higher than their pre-test values for relative V O 2max ( P ≪ 0.001), exercise time ( P ≪ 0.0001), blood lactate concentr . ation ( P ≪ 0.05), RER ( P ≪ 0.01) and RPE ( P ≪ 0.0001); this was also the case for the 60E group for relative V O 2max ( P ≪ 0.01), blood lactate concentration ( P ≪ 0.05), RER ( P ≪ 0.05) and RPE ( P ≪ 0.05). The results suggest that frequent verbal encouragement (every 20 s and 60 s in the present study) leads to significantly greater maximum effort in a treadmill test than when no encouragement is given or when the encouragement is infrequent (i.e. every 180 s).

Comparison of maximal oxygen consumption between black and white prepubertal and pubertal children.

The purpose of this investigation was to determine whether maximal oxygen consumption (VO2max) differed between two selected groups of black and white children and whether a difference existed to determine whether it was related to hematologic profiles, body composition, and/or physical activity/inactivity level. Forty-five prepubertal and 42 pubertal, clinically normal black and white children participated. Dual-energy x-ray absorptiometry was used to determine body composition. A computed tomography scan of the abdomen was used to determine visceral adipose tissue and s.c. adipose tissue. Daily physical activity/inactivity was assessed by questionnaire. Black prepubertal and pubertal children had lower VO2max values when compared with white children (28.8 ± 7.8 versus 35.0 ± 6.5 mL · kg−1 · min−1, p < 0.01; 33.7 ± 6.4 versus 40.4 ± 10.2 mL · kg−1 · min−1, p < 0.05; respectively). Black prepubertal and pubertal children had lower Hb concentrations ([Hb]) and hematocrits than white children (prepubertal: 12.1 ± 0.5 versus 12.8 ± 0.9 g/dL, p < 0.001; 35.6 ± 1.4 versus 37.4 ± 2.3%, p < 0.01, respectively; pubertal: 13.0 ± 0.9 versus 13.6 ± 0.7 g/dL, p < 0.05; 37.7 ± 2.5 versus 39.5 ± 2.1%, p < 0.05, respectively). In conclusion, these findings indicate that black prepubertal and pubertal children had lower VO2max when compared with their white peers matched for age, pubertal stage, and body mass index. This difference in VO2max could be attributed at least in part to comparatively lower [Hb] and more sedentary lifestyle in the black children. Further investigations should study Hb flow rate (a function of [Hb] × maximal cardiac output) in black and white children as it relates to VO2max.

Evaluation of physical activity measured via accelerometry in rural fourth-grade children.

Interest in the benefits of exercise has prompted increased research examining the relationship between physical activity and health status in adults. More recently, considerable research effort has been directed toward the role of physical activity in young children as a precursor to adult physical fitness. The purpose of this study was to estimate the relationship between physical activity measured via accelerometry and body mass index, body mass, body composition, and physical fitness in fourth-grade boys and girls during physical education lessons. 54 fourth-grade students in rural Pennsylvania (28 girls, M age 9.6, SD = .56; 26 boys, M age 9.5, SD = .51) were subjects. Girls were significantly less active during all lessons measured (p<.001). The results of linear regression analyses indicated that physical activity was negatively associated with body mass index, body mass, and body fat percentage (p< .05), and positively associated with physical fitness (V̇O2max) (p<.01). These data indicate the need for curricular intervention to motívate girls to increase their activity during structured physical education lessons and demonstrate the efficacy of the body mass index as a screening tool within the schools.

The effect of acute fluid consumption on measures of impedance and percent body fat using leg-to-leg bioelectrical impedance analysis

Objective:To examine the effect of acute fluid consumption on measures of impedance and percent body fat (%BF) using a common leg-to-leg bioelectrical impedance analyzer system.Design:Cross-sectional design with treatment order determined using a counterbalanced assignment.Setting:University laboratory.Subjects:In total, 21 recreationally active men (mean age 19.7±1.0 years; body mass index 24.2±2.3 kg/m2) volunteered to participate in this study.Intervention:Subjects had their body composition assessed on three separate occasions. After an initial baseline body composition measurement, subjects consumed 591 ml of water (H2O), a carbohydrate/electrolyte drink (CHOE), or received nothing, used as the control (CON). Subjects were reassessed 20, 40, and 60 min after baseline (POST). Urine specific gravity (USG) was recorded at baseline and 60 min POST to assess hydration state.Results:There were no significant changes in impedance or total body water (TBW) for any of the measurement time periods after drinking H2O or a CHOE beverage. Body weight (BW) (P<0.0001) and %BF (P<0.02) increased significantly 20 min POST and remained elevated at the 40 and 60 min POST time periods. After drinking, USG significantly decreased (P<0.0001) 60 min POST from baseline. For the CON trial, there were no significant changes in BW, %BF, TBW, or USG over time.Conclusions:Fluid consumption had no effect on lower-body impedance despite causing significant changes in hydration state. A slight overestimation in %BF (∼0.5%) was observed due to increased BW in the H2O and CHOE trials. This finding may have little practical significance when assessing body composition by LBIA.

The effect of acute fluid consumption on measures of impedance and percent body fat estimated using segmental bioelectrical impedance analysis.

Background/Objectives:To determine the effect of acute fluid consumption on measures of impedance and percent body fat (%BF) estimated using segmental bioelectrical impedance analysis (SBIA).Subjects/Methods:Seventy-six healthy, recreationally active adults (41 women; 35 men) volunteered to participate in this study (mean±s.d.; age, 21.0±1.6 years; body mass index, 25.0±3.2 kg/m2). Subjects had their body composition assessed on three separate occasions. After a baseline measurement, subjects consumed 591 ml of water (H2O), a carbohydrate/electrolyte drink (CHOE) or received nothing (CON). Subjects were reassessed 20, 40 and 60 min following (POST) the baseline measure in each fluid condition.Results:Twenty minutes after drinking a H2O or CHOE beverage, %BF (1.1 and 1.2%), impedance (12 and 14 Ω) and body mass increased significantly (P<0.001). During the CON trial, %BF (0.3 and 0.5%) and impedance (7 and 11 Ω) also increased significantly above baseline values at 40 and 60 min POST. However, the normal hourly variability was significantly (P<0.009) less than the observed fluid-induced %BF alterations. The greatest %BF increases were observed in the lightest subjects, who were women. Fluid type had no effect on the magnitude of change POST.Conclusions:Twenty minutes after drinking, %BF estimates increased approximately 1.0% due to elevations in impedance and body mass. As such, we recommend adhering to the pretest fluid restriction guideline to avoid fluid-induced alterations in SBIA body composition measures. In addition, use of a consistent testing schedule may minimize normal %BF variation over time.

Comparison of Maximal Oxygen Consumption between Obese Black and White Adolescents

Abstract The purpose of this investigation was to determine whether maximal oxygen consumption (VO2max) differed between clinically obese black and white children and if a difference existed to determine whether it was related to hematological profiles and/or physical activity/inactivity levels. Twenty-three black and 21 white adolescents were matched for age, BMI, and Tanner stage (II-V). Body composition was determined by DEXA and CT scan. Daily physical activity/inactivity was assessed by questionnaire. VO2max was assessed using the Bruce treadmill protocol. Black participants had significantly lower VO2max and VO2maxFFM values when compared with white adolescents (26.1 ± 4.2 versus 29.9 ± 3.1 mL · kg−1 · min−1; 48.3 ± 8.8 versus 55.6 ± 5.2 mL · kgFFM−1 · min−1, respectively). Black adolescents also had significantly lower Hb concentrations ([Hb]) than white children (12.7 ± 1.3 versus 13.4 ± 0.7 g/dL). Black adolescents were more physically inactive than their white peers. VO2max correlated with [Hb] for the combined groups. Obese black adolescents had lower VO2max compared with white children and this difference was explained, in part, by the lower [Hb] observed in the black participants. Further investigations should study Hb flow rate (a function of [Hb] · maximal cardiac output) and physical activity/inactivity patterns in obese black and white children as it relates to VO2max.

Effect of resistance exercise on percent body fat using leg-to-leg and segmental bioelectrical impedance analysis in adults.

Dixon, CB and Andreacci, JL. Effect of resistance exercise on percent body fat using leg-to-leg and segmental bioelectrical impedance analysis in adults. J Strength Cond Res 23(7): 2025-2032, 2009-The purpose of this study was to examine the effect of a resistance exercise bout on percent body fat (%BF) measured by leg-to-leg and segmental bioelectrical impedance analysis (LBIA; SBIA) in adults. Eighty-six volunteers (45 women; 41 men) reported to the weight training facility on 2 separate occasions. After an initial LBIA and SBIA assessment, subjects performed 60 minutes of continuous resistance exercise, or did nothing, which served as the control. During the resistance exercise trial, subjects completed an 8-exercise circuit protocol consisting of 3 sets of 10 to 12 repetitions at 65-75% of 1 repetition maximum for each exercise. Subjects were provided with a bottle of water for consumption during both trials. Body composition was reassessed 60 minutes after baseline for comparison. For the resistance exercise trial, significant reductions (p < 0.05) in SBIA-measured %BF (women = 0.9 ± 1.0%; men = 1.4 ± 0.8%) and impedance (women = 22.2 ± 17.0 Ω; men = 22.3 ± 10.0 Ω) were observed, whereas LBIA body composition measurements remained unchanged. After the control trial, significant increases (p < 0.05) in SBIA-measured %BF (women = 0.6 ± 0.8%; men = 0.5 ± 0.7%) and impedance (women = 7.8 ± 12.6 Ω; men = 4.7 ± 8.3 Ω) and LBIA-measured %BF (women = 0.4 ± 0.7%; men = 0.4 ± 0.5%) were observed because of the body mass gain (approximately 300-400 g) after drinking. When using SBIA, assessments should be performed before resistance exercise to eliminate exercise-induced alterations in %BF. Conversely, resistance exercise had no effect on the LBIA measurements, and, therefore, following pretest exercise guidelines may not be necessary when this technology is used for the body composition assessment.