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1.
Int J Sports Med ; 29(1): 53-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17879880

RESUMO

This study sought to determine the influence of 16 months of progressive aerobic exercise on excess postexercise oxygen consumption (EPOC) and the extent EPOC contributed to weight management. Twenty-five overweight/obese women and 16 overweight/obese men participated in a 16-month exercise program (moderate-intensity treadmill walking) that progressed across the first 26 weeks to 5 days.wk(-1), 45 min.session(-1), and 75% HRR. Three-hour EPOC was measured at baseline, 9 months, and 16 months by indirect calorimetry in response to an exercise session (treadmill walking), in which energy expenditure (EE) was estimated from the participant's previous 10 exercise sessions. For women, EPOC was 7.5 +/- 4.9, 9.6 +/- 7.6, and 6.5 +/- 6.5 L at baseline, 9 months, and 16 months, respectively (p > 0.05). For men, EPOC increased from baseline (11.8 +/- 6.8 L) to 9 months (13.5 +/- 8.6 L) (p < 0.05) with no further increase at 16 months (13.5 +/- 11.0 L). Change in EPOC was correlated with change in EE at 9 months (r = 0.65; p < 0.05) and 16 months (r = 0.58; p < 0.05) for men but not women. Progressive long-term exercise significantly influenced EPOC in overweight/obese men but not women. Change in volume of exercise likely explained the increase in energy expenditure during EPOC in men. EPOC contributed modestly to EE compared to the exercise itself.


Assuntos
Metabolismo Energético/fisiologia , Terapia por Exercício , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Adolescente , Adulto , Calorimetria Indireta , Feminino , Humanos , Masculino , Obesidade/fisiopatologia , Obesidade/terapia , Sobrepeso/fisiopatologia , Sobrepeso/terapia , Fatores Sexuais , Fatores de Tempo , Caminhada/fisiologia
2.
Int J Obes (Lond) ; 31(8): 1270-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17325684

RESUMO

OBJECTIVE: To compare the efficacy of a phone vs a traditional face-to-face clinic approach to achieve 10% weight loss and weight maintenance. DESIGN: Twenty-six week, randomized, controlled trial. SUBJECTS: Twenty-four men and 72 women, ages 25-68 years, with a body mass index (BMI) of 33.2+/-3.8. MEASUREMENTS: Weight loss at 12 weeks and weight maintenance at 26 weeks were the primary outcomes. Attendance, meal replacements (MRs), fruits/vegetables (F/V), and physical activity (PA) were measured weekly for process evaluation. RESULTS: Median weight loss (range) from baseline at 12 weeks was significantly different for phone at 10.6 kg (16.6) or 10.4% and clinic at 12.7 kg (19.9) or 13.7%, and both were significantly different when compared with the control group with a weight loss of 0.25 kg (5.6) or 0.24%. Median weight loss at 26 weeks was 12.8 kg (23.4) or 13.0% from baseline for the phone group and 12.5 kg (35.2) or 12.6% from baseline for the clinic group (P>0.05). CONCLUSION: The median weight loss for both phone and clinic groups at 12 and 26 weeks exceeded the NHLBI guideline of 10% weight loss from baseline. The phone approach may be a viable option to the traditional weight management clinic for both service providers and participants.


Assuntos
Entrevistas como Assunto/métodos , Redução de Peso , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/prevenção & controle , Obesidade/terapia , Resultado do Tratamento
3.
Child Care Health Dev ; 31(3): 341-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15840154

RESUMO

BACKGROUND: United States National Health Objectives include increasing the proportion of trips made by walking to and from school for children who live within 1.6 km to 50%. The purpose of this objective is to increase the level of physical activity among children. However, the impact of walking, bicycling or skating (active commuting) to and from school on the prevalence of overweight is unknown. METHODS: Body mass index (BMI) was measured for 320 children (age 10.2+/-0.7 years) in September. Over 5 months, an active commuting index (SI) and daily physical activity were estimated via questionnaire. In April, BMI and body fat were measured. RESULTS: A significant positive association was found between April BMI and SI adjusting for September BMI (partial r=0.03, P<0.05). Positive associations were found between SI and physical activity before school (r=0.17, P<0.05) and daily moderate intensity physical activity (r=0.13, P<0.05). There were no significant association between SI and BF (P>0.05). CONCLUSIONS: This preliminary data suggests that active commuting does not appear to provide sufficient amounts of physical activity to attenuate BMI; however, it may contribute to the attainment of physical activity recommendations. Future research is needed to objectively measure the impact of active commuting on the prevalence of overweight.


Assuntos
Índice de Massa Corporal , Exercício Físico/fisiologia , Meios de Transporte/métodos , Tecido Adiposo , Ciclismo , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Nebraska , Pais/psicologia , Saúde da População Rural , Caminhada
4.
Int J Sports Med ; 26(1): 34-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15643532

RESUMO

Oxygen consumption after exercise is frequently plotted as a function of time and then the area under the curve (AUC) is calculated. Subsequently, this AUC is further manipulated and thus, differences between these manipulations may impact the interpretation of changes in oxygen consumption after exercise. The purpose of this study was to determine if the method of calculating AUC influences the interpretation of changes in post-exercise oxygen consumption in response to long-term aerobic exercise. Forty-three moderately obese, sedentary participants volunteered to participate in this study (26 women and 17 men). All participants performed verified supervised exercise during the study. Supervised treadmill exercise was initially conducted for 3 d/week at 60 % of heart rate reserve (HRR) for 30 min and progressed to 5 d/week at 75 % of HRR for 45 min across the first 4 months. Pre-exercise, exercise, and post-exercise oxygen consumption was measured at baseline and 9 months. AUC was calculated by three methods; total, incremental, and positive incremental. Descriptive statistics and dependent T-tests were calculated for each method of calculating the AUC. In addition, the intra-individual coefficient of variation was determined for each individual for each AUC method. A pearson product moment correlation was calculated for each method to determine the strength of the relationship between pre- and post-training values. The change in post-exercise oxygen AUC after nine months of training was 5.36+/-10.90 L, 2.17+/-7.61 L, and 1.74+/-9.10 L for the total, incremental, and positive incremental methods, respectively. There was significant change in post-exercise total AUC from baseline to 9-months (5.36 +/- 10.90 L), while there was no significant change in incremental or positive incremental AUC. There was a moderately high correlation (r=0.67, p <0.05) between baseline and 9-months for the total AUC method, while there was no significant correlation for incremental and positive incremental AUC methods. These results suggest that the method used to calculate AUC can lead to a different interpretation of the effects of training on post-exercise oxygen consumption. From this data, it appears that analyzing post exercise oxygen consumption with the total area under the curve method has a greater ability to detect a change from aerobic training, than either the positive or incremental area under the curve methods.


Assuntos
Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Medicina Esportiva/métodos , Adaptação Fisiológica/fisiologia , Adulto , Área Sob a Curva , Feminino , Humanos , Masculino
5.
Int J Sports Med ; 24(6): 459-64, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12905096

RESUMO

Few people are active to the levels recommended by Healthy People 2010. Intermittent exercise has been promoted as an exercise prescription which may enable more people to meet recommended guidelines. However, few data are available on intermittent exercise over the long-term. The purpose of the current study was to compare the effects of long-term (72 weeks) continuous (CON) and intermittent (INT) exercise on attrition and adherence in previously sedentary, moderately obese females. Participants were randomized to continuous walking at 60 to 75% of maximum aerobic capacity, 3 days per week, 30 minutes per session, or intermittent exercise for two 15-minute sessions, 5 days per week. Adherence was calculated as the number of sessions completed compared to the number of sessions prescribed. At 12-week intervals, attrition was calculated as the number of participants in the study compared to the total number of participants originally enrolled. For the participants who completed the study, body weight decreased for CON from 80.17 +/- 5.75 kg at baseline to 79.70 +/- 5.40 at 16 months (p < 0.05). For INT, body weight did not change from baseline (85.85 +/- 13.13 kg) to 16 months (85.05 +/- 12.90 kg). By design, INT walked significantly (p < 0.05) further (819 +/- 128 km) compared to CON (527 +/- 46 km). Attrition was 58% for both groups baseline to 72 weeks. However, attrition was greater for CON (38 %) compared to INT (16%) in the first 24 weeks. Adherence was excellent for both groups (> 83%) throughout the study. These results suggest that intermittent and continuous exercise both have considerable attrition rates within 72 weeks of exercise initiation; however, the pattern of attrition differs considerably. That is, it appears that intermittent exercise may reduce attrition in the first 24 weeks of an exercise program; however, attrition does not appear to be different than continuous exercise at 72 weeks.


Assuntos
Exercício Físico , Obesidade , Caminhada , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Cooperação do Paciente
6.
Int J Obes Relat Metab Disord ; 27(8): 912-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12861232

RESUMO

OBJECTIVE: To determine the time course for changes in aerobic capacity, body weight (BW), and composition in overweight adults in response to a supervised exercise trial with a targeted energy expenditure of 2000 kcal week(-1). DESIGN: The Midwest Exercise Trial (MET) was a randomized, controlled, 16-month verified, supervised exercise trial. Aerobic exercise progressed to 45 min day(-1), 5 days week(-1) over 6-months and was then maintained for 10 months. Controls maintained their normal physical activity and all participants maintained ad libitum diets. SUBJECTS: A total of 131 participants were randomized to exercise or control groups and 74 completed the intervention and all laboratory testing. MEASUREMENTS: At baseline and months 4, 9, 12, and 16, aerobic capacity (VO(2max) ) was measured by indirect calorimetry, BW by digital scale, and fat weight and fat-free weight by hydrostatic weighing. RESULTS: Aerobic capacity (ml kg(-1) min(-1)) increased (P<0.05) from baseline (39.2+/-5.2, mean+/-s.d.) to 9 months (48.8+/-4.3) in exercising men as well as women (32.8+/-4.2-39.6+/-5.5) with no significant changes occurring at 12 or 16 months. From baseline to 9 months BW (94.0+/-12.6-88.7+/-9.7 kg) and fat weight (26.8+/-6.8-21.8+/-4.5 kg) significantly decreased in exercising men with no changes occurring at 12 or 16 months. There were no changes in fat-free weight across the 16 months for exercising men or for BW or composition in exercising women. Further, there were no significant changes for the control men for aerobic capacity, BW, or body composition across 16 months. Women in the control group showed significant increases in weight of 2.9+/-5.5 kg and fat weight of 2.1+/-4.8 kg at 16 months only. CONCLUSIONS: We recommend that investigations that use exercise without diet as the stimulus for weight loss have at least a 9-month duration to provide sufficient time for the full effects to be realized, should such effects be present.


Assuntos
Composição Corporal/fisiologia , Exercício Físico/fisiologia , Obesidade/metabolismo , Consumo de Oxigênio/fisiologia , Tecido Adiposo/metabolismo , Adulto , Peso Corporal/fisiologia , Ingestão de Energia/fisiologia , Metabolismo Energético , Feminino , Humanos , Masculino , Fatores de Tempo , Redução de Peso/fisiologia
7.
Int J Obes Relat Metab Disord ; 26(1): 87-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11791151

RESUMO

OBJECTIVE: We examined three methods for calculating the area under the curve (AUC) following an oral glucose tolerance test (OGTT) in overweight adults prior to and after 9 months of exercise. METHOD: Subjects (n=27) were randomly assigned to a control (CON, n=9) or intervention (INT, n=18) group. INT performed supervised exercise 5 days per week, 45 min per session, at 65% of heart rate reserve. OGTTs were administered pre- and post-training. Blood was collected during a 75 g OGTT and analyzed for glucose (GLU) and insulin (INS) concentrations. AUCs were calculated using the incremental, positive incremental, and total AUC methods and the difference scores for pre- and post-training were determined. RESULTS: No differences were observed among the methods for glucose AUC for either group. Significant differences were observed for INT insulin AUC with total AUC (1525+/-3291 microU/1/180 min) significantly greater than incremental AUC (1112+/-3229 microU/1/180 min) or positive incremental AUC (1085+/-3195 microU/I/180 min). Total insulin AUC was significantly reduced following training for INT, while incremental and positive incremental insulin AUCs showed no change. CONCLUSION: These data suggest that the method of used to calculate AUC may affect the interpretation of whether or not an intervention was effective.


Assuntos
Área Sob a Curva , Teste de Tolerância a Glucose/estatística & dados numéricos , Glucose/farmacocinética , Insulina/sangue , Obesidade/metabolismo , Glicemia/metabolismo , Exercício Físico , Humanos
8.
Med Sci Sports Exerc ; 32(7): 1202-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10912882

RESUMO

PURPOSE: The purpose of this investigation was to determine whether muscle damage caused from acute resistance exercise with an eccentric overload would influence resting metabolic rate (RMR) up to 72 h postexercise in resistance-trained (RT) and untrained (UT) subjects. METHODS: Nine RT and 9 UT male subjects (mean +/- SD; age = 20.7 +/- 2.1 yr; body mass = 79.0 +/- 1.4 kg; height = 178.4 +/- 3.1 cm; and body fat = 10.2 +/- 1.6%) were measured for RMR, creatine kinase concentration ([CK]), and rating of perceived muscle soreness (RPMS) on five consecutive mornings. To induce muscle damage, after the measurements on day 2, each subject performed leg presses that emphasized the eccentric movement for 8 sets at his six-repetition maximum (6-RM). RESULTS: Compared with baseline, the RMR (kJ x d(-1) and kJ x kg FFM(-1) x h(-1) was significantly elevated for RT and UT at 24 h and 48 h postexercise. From 24 h to 48 h to 72 h postexercise, RMR significantly decreased within both groups. The UT group had a significantly higher RMR at 24 h (9,705.4 +/- 204.5 kJ x d(-1)) and 48 h postexercise (8,930.9 +/- 104.4 kJ x d(-1)) when compared with the RT group (9,209.3 +/- 535.3 and 8,601.7 + 353.7 kJ x d(-1)). Both [CK] and RPMS showed a similar time course. CONCLUSION: There was a significantly higher [CK] for the UT group at 24 h postexercise (320.4 +/- 20.1 U x L(-1)) and for both [CK] and RPMS at 48 h (1,140.3 +/- 37.1 U x L(-1) and 4.4 +/- 0.5, respectively) and 72 h postexercise (675.9 +/- 41.7 U x L(-1) and 1.67 +/- 0.5, respectively) when compared with the RT group (24 h, 201.9 +/- 13.4 U x L(-1); 48 h, 845.4 +/- 30.7 U x L(-1) and 3.7 +/- 0.5: and 72 h postexercise, 420.2 +/- 70.2 U x L(-1) and 0.89 +/- 0.3). These data indicate that eccentrically induced muscle damage causes perturbations in RMR up to 48 h postexercise.


Assuntos
Exercício Físico/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/patologia , Adolescente , Adulto , Limiar Anaeróbio , Creatina Quinase/metabolismo , Humanos , Masculino
9.
Int J Obes Relat Metab Disord ; 24(5): 566-72, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10849577

RESUMO

OBJECTIVES: To compare the effects of 18 months of continuous vs intermittent exercise on aerobic capacity, body weight and composition, and metabolic fitness in previously sedentary, moderately obese females. DESIGN: Randomized, prospective, long-term cohort study. Subjects performed continuous exercise at 60-75% of maximum aerobic capacity, 3 days per week, 30 min per session, or exercised intermittently using brisk walking for two, 15 min sessions, 5 days per week. MEASURES: Aerobic capacity, body weight, body composition, and metabolic fitness (blood pressure, lipids, glucose and insulin). RESULTS: Significant improvements for aerobic capacity of 8% and 6% were shown for the continuous and intermittent exercise groups, respectively. Weight loss for the continuous exercise group was significant at 2.1% from baseline weight and the intermittent group was essentially unchanged. The continuous group showed a significant decrease in percentage of body fat and fat weight while the intermittent group did not. HDL cholesterol and insulin were significantly improved for both groups. CONCLUSIONS: In previously sedentary, moderately obese females, continuous or intermittent exercise performed long-term may be effective for preventing weight gain and for improving some measures of metabolic fitness.


Assuntos
Composição Corporal , Peso Corporal , Exercício Físico/fisiologia , Obesidade/fisiopatologia , Glicemia/análise , Pressão Sanguínea , Estudos de Coortes , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Insulina/sangue , Lipídeos/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , Redução de Peso
11.
Int J Sport Nutr ; 9(4): 406-15, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10660871

RESUMO

We investigated the effects of carbohydrate ingestion on glycogen replenishment and subsequent short duration, high intensity exercise performance. During Session 1, aerobic power was determined and each subject (N = 6) was familiarized with the 100-kJ cycling test (100KJ-Test). During the treatment sessions, the subjects performed a 100KJ-Test (Ride-1), then consumed 0.7 g.kg body mass-1 of maltodextrin (CHO) or placebo (PLC), rested 60 min, and then performed a second 100KJ-Test (Ride-2). Muscle tissue was collected before (Pre-1) and after Ride-1 (Post-1), and before (Pre-2) and after Ride-2 (Post-2), and analyzed for glycogen concentration. Both treatments yielded a significant increase in glycogen levels following the 60-min recovery, but there was no difference between treatments. Time to complete the 100KJ-Test increased significantly for PLC, but not for CHO. These data indicate that the decrease in performance during Ride-2 in PLC was not the result of a difference in glycogen concentration.


Assuntos
Carboidratos da Dieta/farmacologia , Exercício Físico , Glicogênio/metabolismo , Músculo Esquelético/efeitos dos fármacos , Polissacarídeos/farmacologia , Adulto , Análise de Variância , Bebidas , Ciclismo , Glicemia/metabolismo , Método Duplo-Cego , Humanos , Ácido Láctico/sangue , Masculino , Músculo Esquelético/metabolismo
12.
J Sports Med Phys Fitness ; 38(2): 124-31, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9763797

RESUMO

OBJECTIVES: To evaluate the slow component of VO2 in persons of different fitness levels exercising at different intensities and the contribution of proposed mediators to the slow component of VO2 using equations from the literature. EXPERIMENTAL DESIGN: Cross-sectional. SETTING: University. PARTICIPANTS: Low (N = 15) and high (N = 15) fitness (VO2max of 37 vs 62 ml.min-1.kg-1). INTERVENTIONS: None. MEASURES: Each subject completed, in random order, a series of 12 min cycle ergometer exercise trials corresponding to 50, 60, 70 and 80% of VO2max. VO2, minute ventilation (MV), blood lactate (BL), rectal temperature (RT), heart rate and blood pressure were measured. RESULTS: There was a significant (p < 0.05) increase in the slow component of VO2 for each level of fitness across time and at each workrate. There were no between group differences for any variable. The increase in the slow component of VO2 ranged from 70 ml.min-1 for the lighter workrates to 543 ml.min-1 for the high fitness group at 80% of maximal VO2 (both p < 0.05). The oxygen cost of MV, RT and rate pressure product accounted for about 50% of the observed increase in the slow component of VO2. MV appears to increase in a pattern most similar to the slow component of VO2 and the oxygen cost of MV generally accounted for the highest percentage of the observed increase. CONCLUSIONS: The slow component of VO2 needs to be considered when prescribing exercise. These results are not conclusive concerning the primary mediators of the slow component of VO2.


Assuntos
Consumo de Oxigênio , Aptidão Física/fisiologia , Adulto , Pressão Sanguínea , Temperatura Corporal , Estudos Transversais , Teste de Esforço , Frequência Cardíaca , Humanos , Troca Gasosa Pulmonar
13.
J Am Coll Nutr ; 15(6): 602-7, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8951738

RESUMO

OBJECTIVE: To determine the energy and macronutrient consumption of elementary school children served modified lower fat and sodium or typical higher fat and sodium school lunches. DESIGN: The intervention school received lunches with < 30% of energy from fat and < 1000 mg sodium. The control school received typical lunches with 35% of energy from fat and > 1000 mg sodium. Served lunches were analyzed from menus and consumed lunches were analyzed using USDA plate waste methodology. SUBJECTS: Eighty intervention and 80 control subjects matched for ethnicity and economic status. RESULTS: Intervention school menus were significantly lower for energy, sodium, and fat compared to the control school. From analysis of plate waste, children from both schools consumed approximately 25% less energy than served (p < 0.05). Consumption of fat as a percentage of total energy and consumption of sodium was significantly less for the intervention compared to the control school. Compensation for the lower fat meals by the intervention school children (eating greater portions of high fat items) was not evident as the percentage of energy from fat consumed was only 1.3% greater than the percentage which was served. CONCLUSIONS: Lunch meals in this study were consumed as served. Intervention school children served lower fat and sodium meals consumed less fat and sodium than control school children and did not selectively eat only higher fat and sodium items.


Assuntos
Gorduras na Dieta/administração & dosagem , Ingestão de Energia , Serviços de Alimentação , Sódio na Dieta/administração & dosagem , Criança , Humanos
14.
Obes Res ; 4(3): 229-43, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8732957

RESUMO

Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was approximately 16% less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con.


Assuntos
Ciências da Nutrição/educação , Obesidade/prevenção & controle , Educação Física e Treinamento/organização & administração , Aptidão Física , Serviços de Saúde Escolar/organização & administração , Glicemia/análise , Pressão Sanguínea/fisiologia , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Criança , Colesterol/sangue , Estudos de Coortes , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Ingestão de Energia/fisiologia , Serviços de Alimentação/normas , Humanos , Insulina/sangue , Nebraska/epidemiologia , Obesidade/epidemiologia , Obesidade/fisiopatologia , Educação Física e Treinamento/normas , Fatores de Risco , Serviços de Saúde Escolar/normas , Sódio na Dieta/administração & dosagem , Aumento de Peso/fisiologia
15.
Int J Obes Relat Metab Disord ; 19(6): 382-7, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7550521

RESUMO

OBJECTIVE: It has been suggested that relative heart rate reserve (% HRR), relative oxygen uptake (% VO2peak), and rating of perceived exertion (RPE) can be used interchangeably to prescribe exercise intensity. The purpose of this study was to examine the relationship between % HRR, % VO2peak, and RPE in obese females prior to and following substantial weight loss. SUBJECTS: 122 obese females (% Body fat = 45.9 +/- 5.0%) who participated in a weight loss intervention program. METHOD: Functional aerobic capacity was measured at baseline and following 12 weeks of exercise training and weight loss using a multi-stage Modified Balke treadmill protocol. The VO2, heart rate (HR), and RPE were measured at each stage, with VO2 and HR data converted to the percentages of the peak levels attained. These multi-stage data were then analyzed using mixed-model regression procedures to examine the relationship between % HRR, % VO2, and RPE. RESULTS: With RPE as the dependent variable, results indicated that % HRR and % VO2, corresponded to RPE values consistent with existing guidelines (70% = 13-14 RPE), and this was true for analyses performed at baseline and following weight loss. Further, baseline results indicated that % HRR and % VO2 corresponded to similar levels of exercise intensity (40-70% HRR = 40-70% VO2peak). However, following weight loss, % HRR represented a higher level of intensity than its corresponding % VO2peak. CONCLUSIONS: The results of this study suggest that RPE can be used as subjective marker of exercise intensity in an obese female population. However, despite adhering to existing guidelines prior to weight loss, there may be a discrepancy in the relationship between % HRR and VO2max following severe weight loss, possibly due to the decrease in resting HR following exercise training and weight loss. These findings directly impact the prescription and monitoring of exercise intensity for obese patients.


Assuntos
Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Obesidade/terapia , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Adulto , Estudos Transversais , Teste de Esforço , Feminino , Guias como Assunto , Humanos , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Análise de Regressão , Redução de Peso/fisiologia
16.
Am J Clin Nutr ; 60(6): 874-8, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7985627

RESUMO

This study examined the influence of initial degree of obesity on loss of fat-free mass (FFM). One hundred twelve obese females participated in a series of very-low-energy diet (VLED) clinical trials. Obesity groups were determined by three common methods: percent body fat, body mass index, and weight. Within each group, subjects were classified into low-, intermediate-, and high-obesity groups. As expected, the high-obesity group lost comparable amounts or more weight and more fat weight than the low- and intermediate-obesity classifications for each group. The high-obesity group lost approximately 2% more FFM (P < 0.05) compared with the low and intermediate group when subjects were grouped by body mass index and weight and showed no differences between classifications when subjects were grouped by percent body fat. No differences were found between classifications for ratios of FFM to weight loss regardless of how subjects were grouped. Thus, the degree of obesity does not seem to affect loss of FFM.


Assuntos
Composição Corporal , Dieta Redutora , Ingestão de Energia , Obesidade/dietoterapia , Redução de Peso , Índice de Massa Corporal , Feminino , Humanos , Obesidade/classificação , Obesidade/fisiopatologia
17.
Pancreas ; 9(6): 707-16, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7846013

RESUMO

A prospective, blinded study of CA19-9 in 2,467 patients having abdominal surgery yielded 356 patients with pancreatic, gallbladder, and biliary disease who submitted coded preoperative serum specimens. In this group, there were 84 patients with pancreatic cancer and 24 patients with gallbladder-biliary cancer; the remainder had benign lesions. The recorded imaging data and marker results were merged with the patients' demographic, clinical, and surgical data and tissue diagnoses for analysis. Receiver operator character calculation suggested that a reference value of 100 U/ml for CA19-9 was appropriate rather than the 37-40 U/ml value most frequently employed and yielded a specificity of 97% in the 467 operated patients with a sensitivity of 8.3% for all nonpancreatic-biliary cancers and 62% overall for these lesions. In the more diagnostically challenging nonicteric patients, CA19-9 sensitivity was 55%, specificity was > 99%, positive predictive value (PPV) was 97%, and negative predictive value (NPV) was 88%. When CA19-9 results were combined with those from endoscopic retrograde cholangiopancreatography, ultrasound (US), or computed tomography (CT), the PPV, and especially the NPV were increased. The addition of carcinoembryonic antigen results did not affect overall results. The addition of CA19-9 results to ambiguous or indeterminant imaging interpretation clearly improved the combined specificity, sensitivity, and PPV, but the change was less impressive, albeit positive, for NPV. The combination of CA19-9 and CT (or US) is a reasonable, cost-effective, noninvasive approach to establishing the diagnosis of pancreatic, cholangitic, or biliary cancer in nonicteric patients. Although no single procedure or combination of procedures was found to detect early, small lesions, CA19-9 is clearly a clinically useful adjunct to imaging in nonjaundiced patients suspected of having these malignancies.


Assuntos
Antígeno CA-19-9/sangue , Doenças da Vesícula Biliar/sangue , Doenças da Vesícula Biliar/diagnóstico , Pancreatopatias/sangue , Pancreatopatias/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Antígeno Carcinoembrionário/sangue , Feminino , Seguimentos , Doenças da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/sangue , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/patologia , Humanos , Laparotomia/métodos , Masculino , Pessoa de Meia-Idade , Pancreatopatias/patologia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Estudos Prospectivos , Curva ROC , Fatores de Risco , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Ultrassonografia
18.
Int J Obes Relat Metab Disord ; 18(7): 469-75, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7920872

RESUMO

Obese females undergoing very-low-calorie diet (VLCD) were studied for 12 weeks to determine the effects of concurrent vs delayed and sequential exercise. Subjects were assigned to one of six groups: control (C) n = 28; endurance exercise (EE) n = 18; weight training (WT) n = 26; endurance exercise plus weight training (EEWT) n = 21; control for 4 weeks with subsequent EE (C4EE) n = 10; WT for 4 weeks with sequential EE (WT4EE) n = 12. EE was performed 3 days a week using five weight lifting exercises. Loss in body weight did not differ between groups. Expressed as a ratio of fat-free mass (FFM) to weight loss WT4EE showed a 8.1%, 9.7%, and 11.4% difference compared to EE, C4EE, and C, respectively (P < 0.05). WT4EE also showed significant increases from baseline of 8.2% in aerobic capacity (L/min) and 12.5% in the strength index (SI/kg FFM). WT4EE showed the smallest decrease of all groups in resting metabolic rate of 6.1% of the baseline value; however, this decrease was significant. Although WT4EE showed some favorable changes from baseline, the magnitude of the changes between groups was small. There were no significant differences found between C4EE and the other study groups. Thus, the delay or sequential use of exercise during VLCD provided only small differences for WT4EE compared to the other groups and any clinical significance for the individual is presently unknown.


Assuntos
Dieta Redutora , Exercício Físico , Obesidade/terapia , Composição Corporal , Metabolismo Energético , Teste de Esforço , Feminino , Humanos , Obesidade/metabolismo , Consumo de Oxigênio , Aptidão Física , Fatores de Tempo , Redução de Peso
19.
Int J Obes Relat Metab Disord ; 17(3): 131-7, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8385072

RESUMO

The waist-to-hip ratio (WHR) and the waist circumference have been correlated with blood lipid parameters. However, both the WHR and the waist circumference have been measured in numerous ways by researchers, and it appears that standardization of the anatomical sites used in this measurement is necessary. The present study investigated the associations between five different WHR measurements and blood lipid parameters across age and BMI. Three hundred and twenty-four (324) males were assessed for cholesterol, HDL, LDL, VLDL, cholesterol/HDL ratio, and triglycerides. The waist was identified by three different sites which included the midpoint between the lower rib and iliac crest (ABAB), level of the umbilicus (UMB), and iliac crest (IC). The hip was measured at both the iliac crest (IC) and the greatest girth at the gluteus (GL). A total of five WHRs were calculated from these anatomical measurements. Partial correlation coefficients, controlling for age and BMI, indicated that the ABAB/GL, UMB/GL, ABAB and UMB have the greatest association with all of the blood lipid parameters examined (P < 0.05). However, after stratifying by BMI, partial correlations controlling for age indicated that these significant relationships are only present in the upper quartile of the BMI distribution, indicating that obesity is necessary for these relationships to exist. In addition, risk classification varied according to the WHR which was used. The results indicate that the ABAB/GL, UMB/GL, ABAB and UMB are similar for the prediction of blood lipid parameters. However, the ABAB/GL and ABAB may be the preferred methods because of the consistency in locating the necessary anatomical landmarks.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Tecido Adiposo , Envelhecimento , Composição Corporal , Índice de Massa Corporal , Lipídeos/sangue , Adulto , Antropometria , Colesterol/sangue , Humanos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade
20.
Res Q Exerc Sport ; 63(4): 393-401, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1439164

RESUMO

To characterize hypertrophy and quantify seasonal changes in cardiac structure and function of women collegiate basketball (BB) athletes (n = 15), echocardiographic (echo) measurements were made in the fall (FALL1), winter (WIN), and spring (SPR), then again during the subsequent fall (FALL2; n = 10). Comparisons were made to age-matched nonathletes (NA) measured during FALL1 (n = 22) and SPR (n = 5). Left ventricular (LV) internal dimension-diastole (LVIDd), LV end-diastolic volume (LVEDV), stroke volume (SV), LV mass (LVM), septal thickness (IVS), LV posterior wall thickness (LVPW), right ventricular (RV) internal dimension-diastole (RVIDd), and aortic root diameter (AOD) were significantly larger (12-70%) in the athletes; RVIDd-, LVEDV-, SV-, and LVM-index were also significantly greater (8-46%). From FALL1 to SPR measurement periods, LVIDd, RVIDd, LVEDV, SV, IVS, and LVM-index increased significantly (7-18%) in the athletes. Over the same period of time, LVIDd, LAD, AOD, LVEDV, and SV measured in the five NA subjects increased significantly. In the athletes, LVIDs, RVIDd, IVS, LVPW, and LVM decreased significantly (5-30%) from the SPR to FALL2 measurement period. These data characterize the general nature of the cardiac hypertrophy noted in women BB athletes compared to NA controls and show that distinct changes in heart structure corresponding to different periods of the competitive season can occur in these athletes.


Assuntos
Basquetebol , Coração/anatomia & histologia , Coração/fisiologia , Adulto , Aorta/anatomia & histologia , Aorta/fisiologia , Estatura , Índice de Massa Corporal , Peso Corporal , Ecocardiografia , Exercício Físico/fisiologia , Feminino , Ventrículos do Coração/anatomia & histologia , Humanos , Consumo de Oxigênio/fisiologia , Educação Física e Treinamento , Estações do Ano , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia
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