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1.
Med Sci Sports Exerc ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34559725

RESUMO

INTRODUCTION: Conflicting evidence exists on whether physical activity (PA) levels of humans have changed over the last quarter-century. The main objective of this study was to determine if there is evidence of time trends in PA, from cross-sectional studies that assessed PA at different time points using wearable devices (e.g., pedometers, accelerometers). A secondary objective was to quantify the rate of change in PA. METHODS: A systematic literature review was conducted of English language studies indexed in PubMed, SPORTDiscus, and Web of Science (1960-2020) using search terms (time OR temporal OR secular) AND trends AND (steps per day OR pedometer OR accelerometer OR MVPA). Subsequently, a meta-analytic approach was used to aggregate data from multiple studies, and to examine specific factors (i.e. sex, age group, sex-and-age group, and PA metric). RESULTS: Based on 16 peer-reviewed scientific studies conducted between 1995 and 2017, levels of ambulatory PA are trending downward in developed countries. Significant declines were seen in both males and females (p < 0.001) as well as in children (p = 0.020), adolescents (p < 0.001) and adults (p = 0.004). The average study duration was 9.4 yrs (accelerometer studies: 5.3 yrs, pedometer studies: 10.8 yrs). For studies that assessed steps, the average change in PA was -1,118 steps/day over the course of the study (p < 0.001) and adolescents had the greatest change in PA at -2,278 steps/day (p < 0.001). Adolescents also had the steepest rate of change over time, expressed in steps/day/decade. CONCLUSION: Evidence from studies conducted in eight developed nations over a 22-yr period indicates that PA levels have declined overall, especially in adolescents. This study emphasizes the need for continued research tracking time trends in PA using wearable devices.

2.
J Strength Cond Res ; 35(8): 2165-2169, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34398076

RESUMO

ABSTRACT: Rider, BC, Conger, SA, Ditzenberger, GL, Besteman, SS, Bouret, CM, and Coughlin, AM. Examining the accuracy of the Polar A360 monitor. J Strength Cond Res 35(8): 2165-2169, 2021-The purpose of this study was to determine the accuracy of the Polar A360 heart rate (HR) monitor during periods of rest, walking/running, and active/passive recovery from exercise. Thirty collegiate athletes (women n = 15 and men n = 15) wore an A360 monitor and a previously validated chest HR monitor (Polar RS400) that served as the criterion measurement across a range of resting and walking/running intensities. First, subjects rested in a supine, seated, and standing position. Next, each subject walked on a treadmill at 1.6 kilometers per hour (kph). Speed was increased by 1.6 kph every 2 minutes until volitional fatigue. Then, subjects walked at 4.8 kph followed by a seated recovery stage. Heart rate was recorded in 30-second increments. Total mean difference in HR readings, percent accuracy, and intraclass correlation coefficient (ICC) analysis established the level of agreement between devices. Bland-Altman plots and a regression were used to examine the agreement between devices. The A360 demonstrated a strong correlation with the RS400 (r2 = 0.98) across time points. The analysis of variance with repeated measures indicated an overall significant difference (p < 0.001) between devices. The A360 significantly underestimated HR during the 6.4-kph speed only (p < 0.05) (effect size 0.26). The greatest percent accuracy occurred during rest (91%) and recovery (90%). An ICC of 0.98 (SEM: 0.35) demonstrates a strong level of agreement between devices. The A360 is accurate at rest and during various walking and running speeds and thus is a device that can be used with confidence by athletes for specific training purposes. Future research should examine accuracy during weight training and other sport-specific activities.


Assuntos
Teste de Esforço , Caminhada , Exercício Físico , Feminino , Monitores de Aptidão Física , Frequência Cardíaca , Humanos , Masculino , Monitorização Fisiológica
3.
J Sport Health Sci ; 8(5): 401-411, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31534815

RESUMO

Walking is the most commonly chosen type of physical activity (PA) during pregnancy and provides several health benefits to both mother and child. National initiatives have promoted the importance of walking in general, but little emphasis is directed toward pregnant women, the majority of whom are insufficiently active. Pregnant women face a variety of dynamic barriers to a physically active lifestyle, some of which are more commonly experienced during specific times throughout the pregnancy experience. Walking is unique in that it appears resistant to a number of these barriers that limit other types of PA participation, and it can be meaningfully integrated into some transportation and occupational activities when leisure-time options are unavailable. Preliminary intervention work suggests that walking programs can be effectively adopted into a typical pregnancy lifestyle. However, a great deal of work remains to administer successful pregnancy walking interventions, including developing and using validated methods of PA and walking assessment. This narrative review discusses the unique advantages of walking during pregnancy, provides recommendations for future intervention work, and outlines the need for pregnancy-focused community walking initiatives. Standard search procedures were followed to determine sources from the literature specific to walking during pregnancy for use in each section of this review.

4.
Disabil Health J ; 12(3): 495-502, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30871954

RESUMO

BACKGROUND: Physical function and physical activity decrease with age, but differences in physical activity patterns within different physical functioning groups are unknown. OBJECTIVES: To describe physical activity patterns and multimorbidity burden by physical function group and age. METHODS: Actigraph accelerometer-derived physical activity patterns were compared by physical function (high functioning, activity limitations, activity of daily living disabled) determined by questionnaire and age among 2174 older adults (mean age = 70.9, sd = 0.2 years) from the cross-sectional 2003-2006 National Health and Nutrition Examination Survey. Associations between physical function, physical activity, and multimorbidity were examined. RESULTS: Reduced physical function and increased age were associated with lower physical activity, increased sedentary time and a compressed activity profile. During the most active hour of the day (11:00 a.m.), the oldest, lowest physical functioning group was 82% less active than the youngest, highest physical functioning group. High functioning had over 30% more total activity counts, over 56% more time in moderate-to-vigorous activity, about 8% less time sedentary and took approximately one more sedentary break/hour than lower physical functioning groups. Gender differences in physical activity variables were prevalent for high functioning, but limited within reduced physical functioning groups. Physical function, age, total activity counts/day, and breaks in sedentary time/day were independently associated with multimorbidity (p < 0.005). CONCLUSIONS: Reduced physical function and increased age are associated with physical activity levels, and all three are associated with multimorbidity. Understanding physical activity differences by physical function is important for designing interventions for older individuals at increased risk for mobility disability.


Assuntos
Atividades Cotidianas/psicologia , Envelhecimento/psicologia , Pessoas com Deficiência/psicologia , Pessoas com Deficiência/estatística & dados numéricos , Exercício Físico/psicologia , Multimorbidade , Comportamento Sedentário , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Atividade Motora , Prevalência , Fatores Sexuais , Inquéritos e Questionários
5.
J Strength Cond Res ; 32(9): 2458-2465, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29985226

RESUMO

Dobbs, TJ, Simonson, SR, and Conger, SA. Improving power output in older adults using plyometrics in a body mass-supported treadmill. J Strength Cond Res 32(9): 2458-2465, 2018-The purpose of this study was to determine if performing plyometrics in a body mass-supported treadmill would lead to greater increases in power output and functional strength in older adults compared with traditional strength training. Twenty-three participants were randomized to strength (SG, n = 8), plyometric (PG, n = 8), or control (CG, n = 7) groups. The SG and PG exercised 3 times per week for 8 weeks, whereas the CG performed no exercise. Timed sit-to-stand and stair climb, estimated maximal muscular isotonic strength, and isokinetic strength were assessed pre- and posttraining. Significant improvements occurred in the PG vs. CG in the timed chair sit-to-stand (22.11 ± 8.48%; p = 0.013), timed stair climb (14.68 ± 6.28%; p = 0.002), and stair climb power (16.59 ± 9.07%; p < 0.001). PG and SG significantly increased their estimated 1 repetition maximum in the leg extension and single leg lunge (p < 0.05), and PG was significantly more powerful at all 3 velocities in both flexion and extension compared with SG and CG ranging from 24.54 to 61.85% (p < 0.001) except for 60°·s extension during isokinetic testing. Eight weeks of plyometrics in a body mass-supported treadmill can significantly improve functional strength and power in older adults. In this study, the PG increased muscular strength at the same rate or better than the SG without performing any resistance training. The PG also outperformed SG during the functional tests. These results suggest that plyometrics, if modified and performed in a safe environment, can increase muscular strength and power and improve functional abilities in older adults.


Assuntos
Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Exercício Pliométrico/métodos , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Treinamento de Força/métodos
6.
Appl Physiol Nutr Metab ; 43(5): 531-534, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29272606

RESUMO

The purpose of this study was to investigate blood glucose changes, as measured by a continuous glucose monitoring system, that occur in women with gestational diabetes mellitus (GDM) following an acute bout of moderate-intensity walking after consuming a high-carbohydrate/low-fat meal. This study found that moderate-intensity walking induced greater postprandial glucose control compared with sedentary activity and it appears that moderate-intensity activity may be used to reduce postprandial glucose levels in women with GDM.


Assuntos
Glicemia/metabolismo , Diabetes Gestacional/sangue , Período Pós-Prandial , Caminhada , Adulto , Índice de Massa Corporal , Peso Corporal , Diabetes Gestacional/terapia , Dieta da Carga de Carboidratos , Dieta com Restrição de Gorduras , Feminino , Humanos , Refeições , Gravidez , Terceiro Trimestre da Gravidez , Comportamento Sedentário , Resultado do Tratamento , Adulto Jovem
7.
Med Sci Sports Exerc ; 48(9): 1847-55, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27054678

RESUMO

UNLABELLED: The 2008 Physical Activity Guidelines for Americans recommend that all adults perform muscle-strengthening exercises to work all of the major muscle groups of the body on at least 2 d·wk, in addition to aerobic activity. Studies using objective methods of monitoring physical activity have focused primarily on the assessment of aerobic activity. To date, a method for assessing resistance training (RT) exercises has not been developed using a wrist-worn activity monitor. PURPOSE: The purpose of this study was to examine the use of a wrist-worn triaxial accelerometer-based activity monitor for classifying upper- and lower-body dumbbell RT exercises. METHODS: Sixty participants performed 10 repetitions each of 12 different upper- and lower-body dynamic dumbbell exercises. Algorithms for classifying the exercises were developed using two different methods: support vector machine and cosine similarity. Confusion matrices were developed for each method, and intermethod reliabilities were assessed using Cohen's kappa. A repeated-measures ANOVA was used to compare the predicted repetitions, identified from the largest acceleration peaks, with the actual repetitions. RESULTS: The results indicated that support vector machine and cosine similarity accurately classified the 12 different RT exercises 78% and 85% of the time, respectively. Both methods struggled to correctly differentiate bench press versus shoulder press and squat versus walking lunges. Repetition estimates were not significantly different for 8 of the 12 exercises. For the four exercises that were significantly different, the differences amount to less than 10%. CONCLUSION: This study demonstrated that RT exercises can be accurately classified using a single activity monitor worn on the wrist.


Assuntos
Acelerometria/instrumentação , Treinamento de Força , Adulto , Algoritmos , Feminino , Humanos , Masculino , Máquina de Vetores de Suporte , Punho , Adulto Jovem
8.
J Phys Act Health ; 12(11): 1520-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25635408

RESUMO

BACKGROUND: It is unknown if activity monitors can detect the increased energy expenditure (EE) of wheelchair propulsion at different speeds or on different surfaces. METHODS: Individuals who used manual wheelchairs (n = 14) performed 5 wheeling activities: on a level surface at 3 speeds, on a rubberized track at 1 fixed speed and on a sidewalk course at a self-selected speed. EE was measured using a portable indirect calorimetry system and estimated by an Actical (AC) worn on the wrist and a SenseWear (SW) activity monitor worn on the upper arm. Repeated- measures ANOVA was used to compare measured EE to the estimates from the standard AC prediction equation and SW using 2 different equations. RESULTS: Repeated-measures ANOVA demonstrated a significant main effect between measured EE and estimated EE. There were no differences between the criterion method and the AC across the 5 activities. The SW overestimated EE when wheeling at 3 speeds on a level surface, and during sidewalk wheeling. The wheelchair-specific SW equation improved the EE prediction during low intensity activities, but error progressively increased during higher intensity activities. CONCLUSIONS: During manual wheelchair propulsion, the wrist-mounted AC provided valid estimates of EE, whereas the SW tended to overestimate EE.


Assuntos
Pessoas com Deficiência/estatística & dados numéricos , Metabolismo Energético , Atividade Motora , Cadeiras de Rodas , Acelerometria , Adolescente , Adulto , Idoso , Calorimetria Indireta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
J Phys Act Health ; 12(8): 1102-11, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25347913

RESUMO

BACKGROUND: Increases in childhood and adolescent obesity are a growing concern in the United States (U.S.), and in most countries throughout the world. Declines in physical activity are often postulated to have contributed to the rise in obesity rates during the past 40 years. METHODS: We searched for studies of trends in physical activity and sedentary behaviors of U.S. youth, using nontraditional data sources. Literature searches were conducted for active commuting, physical education, high-school sports, and outdoor play. In addition, trends in sedentary behaviors were examined. RESULTS: Data from the Youth Risk Behavior Surveillance System (YRBSS) and other national surveys, as well as longitudinal studies in the transportation, education, electronic media, and recreation sectors showed evidence of changes in several indicators. Active commuting, high school physical education, and outdoor play (in 3- to 12-year-olds) declined over time, while sports participation in high school girls increased from 1971 to 2012. In addition, electronic entertainment and computer use increased during the first decade of the 21st century. CONCLUSIONS: Technological and societal changes have impacted the types of physical activities performed by U.S. youth. These data are helpful in understanding the factors associated with the rise in obesity, and in proposing potential solutions.


Assuntos
Comportamento do Adolescente/fisiologia , Comportamentos Relacionados com a Saúde , Atividade Motora/fisiologia , Obesidade Pediátrica/epidemiologia , Educação Física e Treinamento/tendências , Comportamento Sedentário , Adolescente , Criança , Feminino , Humanos , Atividades de Lazer , Masculino , Assunção de Riscos , Instituições Acadêmicas , Esportes/fisiologia , Estados Unidos/epidemiologia
10.
Br J Sports Med ; 48(13): 1048-53, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24825852

RESUMO

AIM: To examine the relationship between hand rim propulsion power and energy expenditure (EE) during wheelchair wheeling and to investigate whether adding other variables to the model could improve on the prediction of EE. METHODS: Individuals who use manual wheelchairs (n=14) performed five different wheeling activities in a wheelchair with a PowerTap power meter hub built into the right rear wheel. Activities included wheeling on a smooth, level surface at three different speeds (4.5, 5.5 and 6.5 km/h), wheeling on a rubberised track at one speed (5.5 km/h) and wheeling on a sidewalk course that included uphill and downhill segments at a self-selected speed. EE was measured using a portable indirect calorimetry system. Stepwise linear regression was performed to predict EE from power output variables. A repeated-measures analysis of variance was used to compare the measured EE to the estimates from the power models. Bland-Altman plots were used to assess the agreement between the criterion values and the predicted values. RESULTS: EE and power were significantly correlated (r=0.694, p<0.001). Regression analysis yielded three significant prediction models utilising measured power; measured power and speed; and measured power, speed and heart rate. No significant differences were found between measured EE and any of the prediction models. CONCLUSION: EE can be accurately and precisely estimated based on hand rim propulsion power. These results indicate that power could be used as a method to assess EE in individuals who use wheelchairs.


Assuntos
Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Mãos/fisiologia , Cadeiras de Rodas , Adulto , Fenômenos Biomecânicos/fisiologia , Calorimetria Indireta/instrumentação , Calorimetria Indireta/métodos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Adulto Jovem
11.
Med Sci Sports Exerc ; 46(10): 2025-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24598698

RESUMO

UNLABELLED: The activPAL is an accelerometer-based monitor worn on the thigh that classifies daily activities into three categories (sitting/lying down, standing, and stepping). The monitor discriminates between sitting/lying and the upright position by detecting the inclination of the thigh. It detects stepping from the acceleration versus time wave form. However, a current limitation of the activPAL is that it does not discriminate between sitting and lying down. PURPOSE: This study aimed to determine whether placing a second activPAL monitor on the torso would allow the detection of seated versus lying postures. METHODS: Fifteen healthy adults (18-55 yr of age) wore an activPAL on the right thigh and another activPAL over the right rib cage. Both monitors were synchronized and initialized to record data in 15-s epochs. Participants performed a semistructured routine of activities for 3 min each. Activities included lying down (while supine, prone, and on the side), sitting, standing, sweeping, treadmill walking at 3 mph, and treadmill running at 6 mph. The spatial orientation of the thigh and chest monitors was used to determine body posture, and the activPAL on the thigh was used to detect ambulation. RESULTS: The use of two activPAL devices enabled four behaviors to be accurately classified. The percentages of observations that were classified accurately were as follows: lying down (100%), sitting (100%), standing/light activity in the upright position (90.8%), and stepping (100%). CONCLUSIONS: The current method allows researchers to obtain more detailed information on postural allocation compared with that in the use of a single activPAL on the thigh.


Assuntos
Monitorização Ambulatorial/instrumentação , Postura , Adolescente , Adulto , Humanos , Pessoa de Meia-Idade , Movimento , Decúbito Ventral , Reprodutibilidade dos Testes , Coxa da Perna , Tronco , Adulto Jovem
12.
Med Sci Sports Exerc ; 46(9): 1825-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24496118

RESUMO

PURPOSE: The purpose of this study was to determine the classification accuracy of the waist gravity estimator of normal everyday activity (GENEA) cut-points developed by Esliger et al. for predicting intensity categories across a range of lifestyle activities. METHODS: Each participant performed one of two routines, consisting of seven lifestyle activities (home/office, ambulatory, and sport). The GENEA was worn on the right waist, and oxygen uptake was continuously measured using the Oxycon mobile. A one-way chi-squared test was used to determine the classification accuracy of the GENEA cut-points. Cross-tabulation tables provided information on under- and overestimations, and sensitivity and specificity analyses of the waist cut-points were also performed. RESULTS: Spearman rank order correlation for the GENEA gravity-subtracted signal vector magnitude and Oxycon mobile MET values was 0.73. For all activities combined, the GENEA accurately predicted intensity classification 55.3% of the time, and it increased to 58.3% when stationary cycling was removed from the analysis. The sensitivity of the cut-points for the four intensity categories ranged from 0.244 to 0.958, and the specificity ranged from 0.576 to 0.943. CONCLUSION: In this cross-validation study, the proposed GENEA cut-points had a low overall accuracy rate for classifying intensity (55.3%) when engaging in 14 different lifestyle activities.


Assuntos
Acelerometria/instrumentação , Atividades Cotidianas , Esforço Físico , Esportes/fisiologia , Acelerometria/métodos , Adulto , Basquetebol/fisiologia , Ciclismo/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Consumo de Oxigênio , Valor Preditivo dos Testes , Tênis/fisiologia , Caminhada/fisiologia , Punho
13.
Med Sci Sports Exerc ; 46(1): 201-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23846164

RESUMO

INTRODUCTION: Experts recommend children spend more time playing outdoors. The ambient light sensor of the ActiGraph GT3X+ provides lux measurements. A lux is the International System's unit of illumination, equivalent to 1 lm·m. Few studies have established a lux threshold for determining whether a child is indoors or outdoors. PURPOSE: This study aimed 1) to assess the reliability of the ActiGraph GT3X+ ambient light sensor, 2) to identify a lux threshold to accurately discriminate between indoor and outdoor activities in children, and 3) to test the accuracy of the lux threshold in a free-living environment. METHODS: In part 1, a series of reliability tests were performed using 20 ActiGraph GT3X+ monitors under different environmental conditions. Cronbach's alpha was used to determine interinstrument reliability. In part 2, 18 children performed 11 different activities (five indoors and six outdoors) for 6 min each. The optimal threshold for detecting indoor/outdoor activity was determined using a receiver operator characteristic curve analysis. In part 3, 18 children at a preschool wore the monitor during a school day. Percent accuracy was determined for all conditions. RESULTS: In part 1, the devices had Cronbach's alpha values of 0.992 and 1.000 for indoor and outdoor conditions, respectively, indicating high interinstrument reliability. In part 2, the optimal lux threshold was determined to be 240 lux (sensitivity = 0.92, specificity = 0.88, area under the curve = 0.96, 95% CI = 0.951-0.970). In part 3, results of the school-day validation demonstrated the monitor was 97.0% accurate for overall detection of indoor and outdoor conditions (outdoor = 88.9%, indoor = 99.1%). CONCLUSIONS: The results demonstrate that an ActiGraph GT3X+ lux threshold of 240 can accurately assess indoor and outdoor conditions of preschool children in a free-living environment.


Assuntos
Actigrafia/instrumentação , Monitoramento Ambiental/instrumentação , Luz , Iluminação , Actigrafia/métodos , Criança , Pré-Escolar , Humanos , Jogos e Brinquedos , Curva ROC , Leitura , Reprodutibilidade dos Testes , Televisão , Fatores de Tempo , Caminhada
14.
Med Sci Sports Exerc ; 45(10): 2012-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23584403

RESUMO

PURPOSE: The purpose of this study was to determine whether the published left-wrist cut points for the triaxial Gravity Estimator of Normal Everyday Activity (GENEA) accelerometer are accurate for predicting intensity categories during structured activity bouts. METHODS: A convenience sample of 130 adults wore a GENEA accelerometer on their left wrist while performing 14 different lifestyle activities. During each activity, oxygen consumption was continuously measured using the Oxycon mobile. Statistical analysis used Spearman's rank correlations to determine the relationship between measured and estimated intensity classifications. Cross tabulations were constructed to show the under- or overestimation of misclassified intensities. One-way χ2 tests were used to determine whether the intensity classification accuracy for each activity differed from 80%. RESULTS: For all activities, the GENEA accelerometer-based physical activity monitor explained 41.1% of the variance in energy expenditure. The intensity classification accuracy was 69.8% for sedentary activities, 44.9% for light activities, 46.2% for moderate activities, and 77.7% for vigorous activities. The GENEA correctly classified intensity for 52.9% of observations when all activities were examined; this increased to 61.5% with stationary cycling removed. CONCLUSIONS: A wrist-worn triaxial accelerometer has modest-intensity classification accuracy across a broad range of activities when using the cut points of Esliger et al. Although the sensitivity and the specificity are less than those reported by Esliger et al., they are generally in the same range as those reported for waist-worn, uniaxial accelerometer cut points.


Assuntos
Acelerometria , Gravitação , Monitorização Ambulatorial/instrumentação , Atividade Motora , Esforço Físico , Acelerometria/instrumentação , Adulto , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Consumo de Oxigênio , Esforço Físico/fisiologia , Punho , Adulto Jovem
15.
J Phys Act Health ; 10(4): 556-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22975419

RESUMO

BACKGROUND: The indoor built environment has the potential to influence levels of physical activity. However, the extent to which architectural design in commercial buildings can influence the percentage of people choosing to use the stairs versus elevators is unknown. The purpose of this study was to determine if buildings with centrally located, accessible, and aesthetically pleasing staircases result in a greater percentage of people taking the stairs. METHODS: Direct observations of stair and elevator use were conducted in 3 buildings on a university campus. One of the buildings had a bank of 4 centrally located elevators and a fire escape stairwell behind a steel door. The other 2 buildings had centrally located staircases and out-of-the-way elevators. RESULTS: The percentage of people who ascended the stairs was 8.1% in the elevator-centric building, compared with 72.8% and 81.1% in the 2 stair-centric buildings (P < .001). In addition, the percentage of people who descended the stairs was 10.8% in the first building, compared with 89.5% and 93.7% in the stair-centric buildings (P < .001). CONCLUSIONS: The results of the current study suggest that if buildings are constructed with centrally located, accessible, and aesthetically pleasing staircases, a greater percentage of people will choose to take the stairs.


Assuntos
Elevadores e Escadas Rolantes , Arquitetura de Instituições de Saúde , Atividade Motora , Feminino , Humanos , Masculino , Universidades
16.
Adapt Phys Activ Q ; 28(4): 310-25, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21914904

RESUMO

The purpose of this study was to develop a compendium of wheelchair-related physical activities. To accomplish this, we conducted a systematic review of the published energy costs of activities performed by individuals who use wheelchairs. A total of 266 studies were identified by a literature search using relevant keywords. Inclusion criteria were studies utilizing individuals who routinely use a manual wheelchair, indirect calorimetry as the criterion measurement, energy expenditure expressed as METs or VO2, and physical activities typical of wheelchair users. Eleven studies met the inclusion criteria. A total of 63 different wheelchair activities were identified with energy expenditure values ranging from 0.8 to 12.5 kcal·kg-1·hr-1. The energy requirements for some activities differed between individuals who use wheelchairs and those who do not. The compendium of wheelchair-related activities can be used to enhance scoring of physical activity surveys and to promote the benefits of activity in this population.


Assuntos
Pessoas com Deficiência , Metabolismo Energético/fisiologia , Atividade Motora/fisiologia , Cadeiras de Rodas , Calorimetria Indireta , Humanos
17.
Int J Sport Nutr Exerc Metab ; 21(1): 71-84, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21411838

RESUMO

CONTEXT: Carbohydrate (CHO) and caffeine (CAF) both improve endurance performance. PURPOSE: To determine by systematic literature review coupled with meta-analysis whether CAF ingested with CHO (CHO+CAF) improves endurance performance more than CHO alone. METHODS: Databases were searched using the keywords caffeine, endurance, exercise, carbohydrate, and performance. Criteria for inclusion were studies that used human subjects performing an endurance-exercise performance task and included both a CHO and CHO+CAF condition. Effect sizes (ESs) were calculated as the standardized mean difference. RESULTS: Twenty-one studies met the criteria for analysis. ESs for individual studies ranged from -0.08 (trivial effect favoring CHO) to 1.01 (large effect favoring CHO+CAF). The overall ES equaled 0.26 (95% CI 0.15-0.38, p < .001), indicating that CHO+CAF provides a small but significant performance benefit over CHO. ES was not significantly (p > .05) related to CAF dose, exercise duration, or performance-assessment method. To determine whether ES of CHO+CAF vs. CHO was different than CAF compared with water (placebo), a subgroup meta-analysis compared 36 CAF vs. placebo studies against the 21 CHO+CAF vs. CHO studies. The overall ES for the former group of studies (ES = 0.51, 95% CI 0.40-0.61) was nearly 2-fold greater than in CHO+CAF vs. CHO studies (p = .006). CONCLUSIONS: CHO+CAF ingestion provides a significant but small effect to improve endurance performance compared with CHO alone. However, the magnitude of the performance benefit that CAF provides is less when added to CHO than when added to placebo.


Assuntos
Cafeína/farmacologia , Fármacos do Sistema Nervoso Central/farmacologia , Carboidratos da Dieta/farmacologia , Resistência Física/efeitos dos fármacos , Exercício Físico/fisiologia , Humanos , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/fisiologia , Resistência Física/fisiologia
18.
Curr Sports Med Rep ; 7(4): 193-201, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18607220

RESUMO

Consumption of macronutrients, particularly carbohydrate (CHO) and possibly a small amount of protein, in the early recovery phase after endurance exercise can enhance muscle glycogen resynthesis rates. A target of at least 1.2 g x kg body weight(-1) x h(-1) CHO (over several hours) is suggested. This rate of CHO intake could be sustained with liquid, gel, or solid food rich in CHO for maximizing muscle glycogen. Whether the coingestion of protein with CHO compared with isocaloric CHO results in meaningful differences in glycogen replenishment that translate into subsequent performance enhancement is equivocal. Advantages of added protein with CHO in reducing true muscle damage from endurance exercise remain to be verified. There are, however, no apparent contraindications for using milk or specialty CHO/protein/amino acid products either. Future investigations that examine signaling mechanisms within muscle should be conducted in parallel with translational evidence in humans.


Assuntos
Ingestão de Energia , Resistência Física/fisiologia , Carboidratos da Dieta/metabolismo , Proteínas na Dieta/metabolismo , Glicogênio/metabolismo , Humanos , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Fatores de Tempo
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