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1.
Sci Rep ; 14(1): 4334, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383561

RESUMEN

Riding a bicycle is considered a durable skill that cannot be forgotten. Here, novice participants practiced riding a reversed bicycle, in which a reversing gear inverted the handlebar's rotation. Although learning to ride the reversed bicycle was possible, it was slow, highly variable, implicit, and followed an S-shape pattern. In the initial learning phase, failed attempts to ride the normal bicycle indicated strong interference between the two bicycle skills. While additional practice decreased this interference effect, a subset of learners could not ride either bicycle after eight sessions of practice. Experienced riders who performed extensive practice could switch bicycles without failed attempts and exhibited similar performance (i.e., similar handlebar oscillations) on both bicycles. However, their performance on the normal bicycle was worse than that of the novice bicycle riders at baseline. In conclusion, "unlearning" of the normal bicycle skill precedes the initial learning of the reversed bicycle skill, and a signature of such unlearning is still present following extensive practice.


Asunto(s)
Ciclismo , Investigación , Humanos
2.
Neurosci Insights ; 17: 26331055221119441, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35983377

RESUMEN

Resistance training is a promising strategy to promote healthy cognitive aging; however, the brain mechanisms by which resistance training benefits cognition have yet to be determined. Here, we examined the effects of a 12-week resistance training program on resting brain activity and cerebrovascular function in 20 healthy older adults (14 females, mean age 69.1 years). In this single group clinical trial, multimodal 3 T magnetic resonance imaging was performed at 3 time points: baseline (preceding a 12-week control period), pre-intervention, and post-intervention. Along with significant improvements in fluid cognition (d = 1.27), 4 significant voxelwise clusters were identified for decreases in resting brain activity after the intervention (Cerebellum, Right Middle Temporal Gyrus, Left Inferior Parietal Lobule, and Right Inferior Parietal Lobule), but none were identified for changes in resting cerebral blood flow. Using a separate region of interest approach, we provide estimates for improved cerebral blood flow, compared with declines over the initial control period, in regions associated with cognitive impairment, such as hippocampal blood flow (d = 0.40), and posterior cingulate blood flow (d = 0.61). Finally, resistance training had a small countermeasure effect on the age-related progression of white matter lesion volume (rank-biserial = -0.22), a biomarker of cerebrovascular disease. These proof-of-concept data support larger trials to determine whether resistance training can attenuate or even reverse salient neurodegenerative processes.

3.
Phys Ther ; 102(5)2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35225349

RESUMEN

Although Parkinson disease (PD) has traditionally been considered a disease of the central nervous system, a bidirectional communication system known as the gut-brain axis can influence PD pathogenesis. The dual-hit hypothesis proposed that PD is due to peripheral dysregulations to the gut microbiota, known as dysbiosis. Since then, further investigation has shown that there are multiple pathological sources associated with PD. However, dysbiosis plays a critical role in the disease process. Substantial evidence has identified that cardinal motor symptoms of PD and disease progression are associated with dysbiosis. In other neurodegenerative disorders, dysbiosis has been linked to cognition. Non-PD research has shown that exercise can effectively restore the gut microbiota. Likewise, exercise has become a well-established strategy to improve cognitive and motor function in PD. However, despite the interaction between the gut and brain, and the exercise benefits on gut health, no research to date has considered the effects of exercise on the gut microbiota in PD. Therefore, the purpose of this Perspective is to explore whether exercise benefits observed in PD could partly be due to restorations to the gut microbiota. First, we will review the gut-brain axis and its influence on motor and cognitive function. Next, we will outline evidence regarding exercise-induced restoration of the gut microbiota in non-PD populations. Finally, we will summarize benefits of exercise on motor-cognitive function in PD, proposing that benefits of exercise seen in PD might actually be due to restorations to the gut microbiota. By positing the gut microbiota as a moderator of exercise improvements to motor and cognitive function, we aim to provide a new perspective for physical therapists to prioritize exercise regimens for individuals with PD that can specifically restore the gut microbiota to better improve PD symptoms and prognosis. IMPACT: This Perspective raises awareness that dysregulations to the gut microbiota have recently been attributed to PD symptoms and pathology and that exercise can be an effective therapeutic strategy to improve gut health in individuals with PD. LAY SUMMARY: People with PD have been found to have reduced microbial diversity in their gut, which can play an important role in the progression of the disease. Physical therapists can design therapeutic exercises that might help improve gut health in people with PD.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad de Parkinson , Encéfalo , Disbiosis/patología , Ejercicio Físico , Microbioma Gastrointestinal/fisiología , Humanos
4.
PLoS One ; 16(7): e0255018, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34293060

RESUMEN

OBJECTIVES: Resistance training (RT) is a promising strategy to slow or prevent fluid cognitive decline during aging. However, the effects of strength-specific RT programs have received little attention. The purpose of this single-group proof of concept clinical trial was to determine whether a 12-week strength training (ST) program could improve fluid cognition in healthy older adults 60 to 80 years of age, and to explore concomitant physiological and psychological changes. METHODS: Twenty participants (69.1 ± 5.8 years, 14 women) completed this study with no drop-outs or severe adverse events. Baseline assessments were completed before an initial 12-week control period, then participants were re-tested at pre-intervention and after the 12-week ST intervention. The NIH Toolbox Cognition Battery and standard physical and psychological measures were administered at all three time points. During the 36 sessions of periodized ST (3 sessions per week), participants were supervised by an exercise specialist and challenged via autoregulatory load progression. RESULTS: Test-retest reliability over the control period was good for fluid cognition and excellent for crystallized cognition. Fluid composite scores significantly increased from pre- to post-intervention (8.2 ± 6.1%, p < 0.01, d = 1.27), while crystallized composite scores did not (-0.5 ± 2.8%, p = 0.46, d = -0.34). Performance on individual fluid instruments, including executive function, attention, working memory, and processing speed, also significantly improved. Surprisingly, changes in fluid composite scores had small negative correlations with changes in muscular strength and sleep quality, but a small positive correlation with changes in muscular power. CONCLUSIONS: Thus, improvements in fluid cognition can be safely achieved in older adults using a 12-week high-intensity ST program, but further controlled studies are needed to confirm these findings. Furthermore, the relationship with other widespread physiological and psychological benefits remains unclear.


Asunto(s)
Cognición/fisiología , Entrenamiento de Fuerza , Anciano , Femenino , Humanos , Masculino , Proyectos Piloto , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Resultado del Tratamiento
5.
Artículo en Inglés | MEDLINE | ID: mdl-35928984

RESUMEN

The outbreak of severe acute respiratory syndrome coronavirus 2, also known as Coronavirus Disease 2019 (COVID-19) sparked a global public health pandemic that has impacted every aspect of daily life. Medical research was affected, and many clinical trials were halted to minimize COVID-19 transmission risk and spread while the world navigated this novel virus. Here we describe the relaunch of our virtual reality (VR) pilot clinical trial that uses an in-lab brain and body training program to promote brain health in mid-to-late life older adults, in the era of COVID-19. This case series includes five healthy female participants between 51 and 76 years of age, a subset of a larger VR pilot clinical trial that started pre-pandemic. We developed a revised study protocol based on the Center for Disease Control and World Health Organization guidelines to help manage the spread of COVID-19. Since the limited resumption of clinical trials at our institution in August 2020, we successfully completed over 200 in-lab virtual reality training sessions using our revised protocol. During this time, none of the five participants or three study staff reported any COVID-19 symptoms or reported a positive COVID-19 test. More than 40 voluntary COVID-19 tests were completed by our study staff over the last 6 months. All participants rated our safety protocol as very satisfied or extremely satisfied and that they would be very likely or extremely likely to participate in a VR clinical trial during the pandemic. Based on these findings, we suggest that continued VR clinical trial research during the COVID-19 pandemic is achievable and can be safely resumed if specific safety protocols are in place to mitigate the risk of exposure and spread of COVID-19.

6.
Sports (Basel) ; 8(12)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33266118

RESUMEN

Maximal oxygen uptake (VO2max) and critical speed (CS) are key fatigue-related measurements that demonstrate a relationship to one another and are indicative of athletic endurance performance. This is especially true for those that participate in competitive fitness events. However, the accessibility to a metabolic analyzer to accurately measure VO2max is expensive and time intensive, whereas CS may be measured in the field using a 3 min all-out test (3MT). Therefore, the purpose of this study was to examine the relationship between VO2max and CS in high-intensity functional training (HIFT) athletes. Twenty-five male and female (age: 27.6 ± 4.5 years; height: 174.5 ± 18.3 cm; weight: 77.4 ± 14.8 kg; body fat: 15.7 ± 6.5%) HIFT athletes performed a 3MT as well as a graded exercise test with 48 h between measurements. True VO2max was determined using a square-wave supramaximal verification phase and CS was measured as the average speed of the last 30 s of the 3MT. A statistically significant and positive correlation was observed between relative VO2max and CS values (r = 0.819, p < 0.001). Based on the significant correlation, a linear regression analysis was completed, including sex, in order to develop a VO2max prediction equation (VO2max (mL/kg/min) = 8.449(CS) + 4.387(F = 0, M = 1) + 14.683; standard error of the estimate = 3.34 mL/kg/min). Observed (47.71 ± 6.54 mL/kg/min) and predicted (47.71 ± 5.7 mL/kg/min) VO2max values were compared using a dependent t-test and no significant difference was displayed between the observed and predicted values (p = 1.000). The typical error, coefficient of variation, and intraclass correlation coefficient were 2.26 mL/kg/min, 4.90%, and 0.864, respectively. The positive and significant relationship between VO2max and CS suggests that the 3MT may be a practical alternative to predicting maximal oxygen uptake when time and access to a metabolic analyzer is limited.

7.
Vasc Health Risk Manag ; 16: 133-142, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32308406

RESUMEN

OBJECTIVE: A new automated and adjustable blood pressure (BP) system has been developed to improve the accuracy of BP measurements on public-use health stations. This self-fitting BP system includes a mechanical cuff that wraps down to the user's arm prior to bladder inflation. The purpose of this study was to validate the adaptable BP system (ABPS) using the current standards from the Association for the Advancement of Medical Instrumentation (AAMI). METHODS: The AAMI/ISO 81060:2013 standards for clinical validation of non-invasive automated arterial BP measurement devices were followed precisely using the same arm sequential method. For each participant, BP was measured over multiple trials by trained observers alternating a reference sphygmomanometer with the ABPS. All study requirements were met with 85 qualifying participants, each with 3 valid paired determinations. RESULTS: The mean difference between ABPS BP and reference BP using all 255 paired determinations was -2.4 ± 7.7 mmHg for systolic and 1.7 ± 5.7 mmHg for diastolic. The standard deviation of the averaged paired determinations per participant was 6.3 mmHg for systolic and 5.2 mmHg for diastolic. Arm circumference measurements had a mean error of -2.1 ± 2.4 cm (R2 = 0.87). A new prediction model for arm circumference was validated using a holdout dataset (R2 = 0.94). CONCLUSION: The results of the study confirm that the ABPS met all benchmarks established by the AAMI. The device accurately measures BP across a wide range of arm circumferences (24-44 cm) and is suitable for use by individuals to self-monitor BP.


Asunto(s)
Brazo/irrigación sanguínea , Determinación de la Presión Sanguínea/instrumentación , Presión Sanguínea , Hipertensión/diagnóstico , Salud Pública/instrumentación , Adolescente , Adulto , Anciano , Automatización , California , Diseño de Equipo , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Adulto Joven
8.
Phys Ther ; 100(6): 907-916, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-31944253

RESUMEN

The prevalence of dementia and other age-associated cognitive disorders is steadily increasing worldwide. With no cure after diagnosis, successful treatment likely requires maximum adherence to preventative countermeasures. Many potential risk factors are modifiable through exercise. Specifically, mounting evidence suggests that long-term resistance training (RT) can help maintain cognitive abilities with aging and have additional benefits to overall brain health. Physical therapists are uniquely positioned to administer such clinical interventions designed to slow disease progression. However, a neuroscientific foundation for these benefits must be established to justify the integration of RT for brain health into practice. The mechanisms of cognitive decline are commonly linked to fundamental processes of aging. Even healthy older adults experience decreases in physical capacity, vascular function, brain structure and function, glucose regulation, inflammation, mood, and sleep quality. Yet, clinical trials involving RT in older adults have consistently demonstrated improvements in each of these systems with concomitant enhancement of cognitive performance. Beneficial adaptations may indirectly or directly mediate benefits to brain function, and understanding this relationship can help us develop optimal intervention strategies for the aging population.


Asunto(s)
Refuerzo Biomédico/métodos , Trastornos del Conocimiento/prevención & control , Cognición/fisiología , Entrenamiento de Fuerza/métodos , Adaptación Fisiológica , Afecto/fisiología , Anciano , Glucemia/metabolismo , Encéfalo/anatomía & histología , Encéfalo/fisiología , Circulación Cerebrovascular/fisiología , Disfunción Cognitiva/rehabilitación , Humanos , Inflamación/fisiopatología , Inflamación/prevención & control , Fuerza Muscular/fisiología , Rendimiento Físico Funcional , Sueño/fisiología , Factores de Tiempo
9.
J Pediatr Endocrinol Metab ; 32(10): 1121-1129, 2019 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-31539362

RESUMEN

Introduction Growing evidence indicates that circulating concentrations of insulin-like growth factor 1 (IGF-I), along with IGF-I relative to IGF-binding proteins (IGFBP), are associated with an increased risk of cancer. In accord, regular exercise is linked with a lower risk of cancer. Purpose To assess the effects of a 16-week home-based strength training (HBST) program on serum IGF-I, IGFBP-1 and IGFBP-3. Methods A total of 32 obese Latino adolescent males (aged 14-18 years) were randomized into a twice-weekly HBST (n = 16) or a control group (C, n = 16) for 16 weeks. The following were measured at pre- and post-intervention: IGF-I, IGFBP-1 and IGFBP-3, glucose/insulin indices by oral and/or intravenous (IV) glucose tolerance tests, strength by one-repetition maximum (1RM), dietary intake by 3-d records, body composition by DEXA and physical activity using the Actigraph GT1X. The generalized linear model (GLM) was used to assess differences in changes among outcome measures between the HBST and C groups. Results Exercise adherence in the HBST group was 89%. IGF-1 showed a trend for significant within-subject improvements (p = 0.078) but no significant within-subject or between-subject differences for IGFBP-1, IGFBP-3 two-glucose, fasting glucose or 2-h glucose (p > 0.05). There was a significant decrease (p > 0.05) in fasting glucose in the C group (p = 0.02) and also in the intervention group (p = 0.03) between baseline and follow-up testing. A significant difference was also found in the C group for 2-h glucose with an increase at follow-up testing (p = 0.04). Conclusions Though not statistically significant (p < 0.05), the results indicated that a 16-week HBST program decreased IGF-I and increased IGFBP-1, along with IGFBP-3, concentrations among overweight/obese Latino boys. However, further studies should consider increasing either the dose or the duration of the intervention to elicit greater improvements in this at-risk pediatric population.


Asunto(s)
Biomarcadores/sangre , Ejercicio Físico , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Obesidad/sangre , Entrenamiento de Fuerza , Adolescente , Composición Corporal , Estudios de Casos y Controles , Estudios de Seguimiento , Prueba de Tolerancia a la Glucosa , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Obesidad/fisiopatología , Obesidad/terapia , Pronóstico
10.
Sports (Basel) ; 7(4)2019 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-31013585

RESUMEN

CrossFit® began as another exercise program to improve physical fitness and has rapidly grown into the "sport of fitness". However, little is understood as to the physiological indicators that determine CrossFit® sport performance. The purpose of this study was to determine which physiological performance measure was the greatest indicator of CrossFit® workout performance. Male (n = 12) and female (n = 5) participants successfully completed a treadmill graded exercise test to measure maximal oxygen uptake (VO2max), a 3-minute all-out running test (3MT) to determine critical speed (CS) and the finite capacity for running speeds above CS (D'), a Wingate anaerobic test (WAnT) to assess anaerobic peak and mean power, the CrossFit® total to measure total body strength, as well as the CrossFit® benchmark workouts: Fran, Grace, and Nancy. It was hypothesized that CS and total body strength would be the greatest indicators of CrossFit® performance. Pearson's r correlations were used to determine the relationship of benchmark performance data and the physiological performance measures. For each benchmark-dependent variable, a stepwise linear regression was created using significant correlative data. For the workout Fran, back squat strength explained 42% of the variance. VO2max explained 68% of the variance for the workout Nancy. Lastly, anaerobic peak power explained 57% of the variance for performance on the CrossFit® total. In conclusion, results demonstrated select physiological performance variables may be used to predict CrossFit® workout performance.

11.
Physiother Theory Pract ; 35(5): 489-494, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-29482413

RESUMEN

Patients who have undergone unicompartmental knee arthroplasty (UKA) have been reported to exhibit altered gait 19-25 months post-surgery. The most common gait impairment in this population is inadequate knee flexion and a corresponding decrease in the knee extensor moment during loading response (i.e., quadriceps avoidance). The purpose of this case series was to determine whether incorporation of antigravity treadmill training into a standard physical therapy program can eliminate quadriceps avoidance gait during the early rehabilitation phase following UKA. Four females who underwent UKA were recruited for this study. Participants completed antigravity treadmill training three times per week for 12 weeks in addition to their standard physical therapy program. Instrumented gait analysis was performed at baseline (pre-intervention), week 6 (mid-intervention), and week 12 (post-intervention). We found that peak knee flexion and the peak knee extensor moment during the weight acceptance phase of gait increased to normal values following the 12-week intervention period (14.1 ± 6.5° to 20.6 ± 1.5° and 0.4 ± 0.3 to 0.7 ± 0.2 Nm/kg respectively). The findings of this case series suggest that a standard physical therapy program that incorporates early gait training using an antigravity treadmill may be beneficial in eliminating "quadriceps avoidance" during the early rehabilitation phase following UKA.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/rehabilitación , Terapia por Ejercicio/métodos , Marcha , Gravitación , Articulación de la Rodilla/cirugía , Anciano , Fenómenos Biomecánicos , Diseño de Equipo , Terapia por Ejercicio/instrumentación , Femenino , Humanos , Articulación de la Rodilla/fisiopatología , Persona de Mediana Edad , Músculo Cuádriceps/fisiopatología , Rango del Movimiento Articular , Recuperación de la Función , Factores de Tiempo , Resultado del Tratamiento , Soporte de Peso
12.
Orthop J Sports Med ; 5(8): 2325967117722794, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28840147

RESUMEN

BACKGROUND: Rehabilitation after repair of the anterior cruciate ligament (ACL) is complicated by the loss of leg muscle mass and strength. Prior studies have shown that preoperative rehabilitation may improve muscle strength and postoperative outcomes. Testosterone supplementation may likewise counteract this muscle loss and potentially improve clinical outcomes. PURPOSE: The purpose was to investigate the effect of perioperative testosterone administration on lean mass after ACL reconstruction in men and to examine the effects of testosterone on leg strength and clinical outcome scores. It was hypothesized that testosterone would increase lean mass and leg strength and improve clinical outcome scores relative to placebo. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Male patients (N = 13) scheduled for ACL reconstruction were randomized into 2 groups: testosterone and placebo. Participants in the testosterone group received 200 mg of intramuscular testosterone weekly for 8 weeks beginning 2 weeks before surgery. Participants in the placebo group received saline following the same schedule. Both groups participated in a standard rehabilitation protocol. The primary outcome was the change in total lean body mass at 6 and 12 weeks. Secondary outcomes were extensor muscle strength, Tegner activity score, and Knee injury and Osteoarthritis Outcome Score. RESULTS: There was an increase in lean mass of a mean 2.7 ± 1.7 kg at 6 weeks postoperatively in the testosterone group compared with a decrease of a mean 0.1 ± 1.5 kg in the placebo group (P = .01). Extensor muscle strength of the uninjured leg also increased more from baseline in the testosterone group (+20.8 ± 25.6 Nm) compared with the placebo group (-21.4 ± 36.7 Nm) at 12 weeks (P = .04). There were no significant between-group differences in injured leg strength or clinical outcome scores. There were no negative side effects of testosterone noted. CONCLUSION: Perioperative testosterone supplementation increased lean mass 6 weeks after ACL reconstruction, suggesting that this treatment may help minimize the effects of muscle atrophy associated with ACL injuries and repair. This study was not powered to detect differences in strength or clinical outcome scores to assess the incidence of testosterone-related adverse events. CLINICAL RELEVANCE: Supraphysiological testosterone supplementation may be a useful adjunct therapy for counteracting muscle atrophy after ACL reconstruction. Further investigation is necessary to determine the safety profile and effects of perioperative testosterone administration on leg strength and clinical outcomes after surgery. REGISTRATION: NCT01595581 (ClinicalTrials.gov).

13.
Res Q Exerc Sport ; 88(2): 193-202, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28388333

RESUMEN

PURPOSE: Acute muscle damage after exercise triggers subsequent regeneration, leading to hypertrophy and increased strength after repeated exercise. It has been debated whether acute exercise-induced muscle damage is altered under various premenopausal estrogen conditions. Acute contraction-induced muscle damage was compared during exogenous (oral contraceptive, OC), endogenous (luteal phase, HI), or low (menses, LO) estrogen in healthy young women aged 21 to 30 years old. METHODS: Women (OC, n = 9; HI, n = 9; LO, n = 8; total N = 26) performed 1 neuromuscular electrical stimulation (NMES) bout. Soreness, measured via visual analog scale and the Likert Scale of Muscle Soreness for Lower Limb (LSMSLL), quadriceps strength, and plasma myoglobin (Mb), interleukin (IL)-6, IL-8, and granulocyte-colony stimulating factor were measured before and after NMES. RESULTS: NMES performance was similar across groups. Meaningful within-group increases in Mb (effect size [ES] = 1.12) and IL-8 (ES = 0.38) occurred in LO; ES for HI and OC were trivial. ES of the between-group difference in change was moderate for Mb (LO vs. HI = 1.15) and IL-8 (LO vs. HI = 0.86; LO vs. OC = 0.73). 17-ß estradiol correlated moderately and negatively with Mb relative change (r = -.52, p < .05). LO had ~5% greater strength loss than OC and HI. The mean change score for the LSMSLL 2 days post-NMES was clinically greater in LO than OC or HI. CONCLUSIONS: Acute NMES-induced indicators of muscle fiber damage and qualitative muscle soreness may be attenuated during the luteal phase or active OC pill consumption compared with the menstrual phase.


Asunto(s)
Anticonceptivos Hormonales Orales/administración & dosificación , Estradiol/sangre , Ejercicio Físico/fisiología , Fase Luteínica/fisiología , Mialgia/fisiopatología , Mioglobina/sangre , Adulto , Composición Corporal/fisiología , Estimulación Eléctrica , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/sangre , Humanos , Interleucina-6/sangre , Interleucina-8/sangre , Contracción Isométrica/fisiología , Adulto Joven
14.
Int J Med Sci ; 12(6): 494-501, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26078710

RESUMEN

PURPOSE: With the childhood obesity epidemic, efficient methods of exercise are sought to improve health. We tested whether whole body vibration (WBV) exercise can positively affect bone metabolism and improve insulin/glucose dynamics in sedentary overweight Latino boys. METHODS: Twenty Latino boys 8-10 years of age were randomly assigned to either a control (CON) or 3 days/wk WBV exercise (VIB) for 10-wk. RESULTS: Significant increases in BMC (4.5 ± 3.2%; p=0.01) and BMD (1.3 ± 1.3%; p<0.01) were observed for the VIB group when compared to baseline values. For the CON group BMC significantly increased (2.0 ± 2.2%; p=0.02), with no change in BMD (0.8 ± 1.3%; p=0.11). There were no significant between group changes in BMC or BMD. No significant change was observed for osteocalcin and (collagen type I C-telopeptide) CTx for the VIB group. However, osteocalcin showed a decreasing trend (p=0.09) and CTx significantly increased (p<0.03) for the CON group. This increase in CTx was significantly different between groups (p<0.02) and the effect size of between-group difference in change was large (-1.09). There were no significant correlations between osteocalcin and measures of fat mass or insulin resistance for collapsed data. CONCLUSION: Although bone metabolism was altered by WBV training, no associations were apparent between osteocalcin and insulin resistance. These findings suggest WBV exercise may positively increase BMC and BMD by decreasing bone resorption in overweight Latino boys.


Asunto(s)
Biomarcadores/metabolismo , Obesidad/metabolismo , Sobrepeso/metabolismo , Vibración , Adulto , Densidad Ósea , Niño , Ejercicio Físico , Hispánicos o Latinos , Humanos , Resistencia a la Insulina/genética , Masculino , Obesidad/fisiopatología , Obesidad/terapia , Osteocalcina/genética , Osteocalcina/metabolismo , Sobrepeso/fisiopatología , Sobrepeso/terapia , Distribución Aleatoria
15.
J Pediatr Endocrinol Metab ; 28(3-4): 315-22, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25781537

RESUMEN

OBJECTIVE: To determine the effects of a home-based strength training (HBST) intervention on insulin sensitivity (SI), compensatory acute insulin response and ß-cell function, body composition measures, and maximum strength in obese Latino boys. METHODS: A total of 26 obese Latino males aged between 14 and 18 years were randomized to either a twice-weekly (n=15) or a control group (C; n=15) for 16 weeks. HBST for 16 weeks, composed of two 1-h sessions per week. Outcome measures were assessed pre-and post-intervention/control condition and included SI, acute insulin response to glucose (AIR) and disposition index (DI), fasting glucose, 2-h glucose, body composition using waist-hip circumferences, body mass index (BMI), dual energy X-ray absorptiometry (DEXA) scan, blood pressure, and strength by 1-repetition maximum. A repeated measures GLM was used to assess differences in changes in outcome measures, between the C and the HBST groups. RESULTS: There were no significant overall intervention effects on any of the outcome variables (p<0.05). CONCLUSION: These results suggest that an HBST does not improve SI, maximal strength or decrease adiposity in obese Latino boys.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Hispánicos o Latinos , Servicios de Atención de Salud a Domicilio , Obesidad Infantil/complicaciones , Obesidad Infantil/terapia , Entrenamiento de Fuerza/métodos , Absorciometría de Fotón , Adolescente , Composición Corporal , Diabetes Mellitus Tipo 2/etnología , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/prevención & control , Prueba de Tolerancia a la Glucosa , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Resistencia a la Insulina , Masculino , Obesidad Infantil/etnología , Obesidad Infantil/metabolismo , Factores Sexuales
16.
J Athl Train ; 50(4): 407-18, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25611315

RESUMEN

CONTEXT: Self-report questionnaires are an important method of evaluating lifespan health, exercise, and health-related quality of life (HRQL) outcomes among elite, competitive athletes. Few instruments, however, have undergone formal characterization of their psychometric properties within this population. OBJECTIVE: To evaluate the validity and reliability of a novel health and exercise questionnaire, the Trojan Lifetime Champions (TLC) Health Survey. DESIGN: Descriptive laboratory study. SETTING: A large National Collegiate Athletic Association Division I university. PATIENTS OR OTHER PARTICIPANTS: A total of 63 university alumni (age range, 24 to 84 years), including former varsity collegiate athletes and a control group of nonathletes. INTERVENTION(S): Participants completed the TLC Health Survey twice at a mean interval of 23 days with randomization to the paper or electronic version of the instrument. MAIN OUTCOME MEASURE(S): Content validity, feasibility of administration, test-retest reliability, parallel-form reliability between paper and electronic forms, and estimates of systematic and typical error versus differences of clinical interest were assessed across a broad range of health, exercise, and HRQL measures. RESULTS: Correlation coefficients, including intraclass correlation coefficients (ICCs) for continuous variables and κ agreement statistics for ordinal variables, for test-retest reliability averaged 0.86, 0.90, 0.80, and 0.74 for HRQL, lifetime health, recent health, and exercise variables, respectively. Correlation coefficients, again ICCs and κ, for parallel-form reliability (ie, equivalence) between paper and electronic versions averaged 0.90, 0.85, 0.85, and 0.81 for HRQL, lifetime health, recent health, and exercise variables, respectively. Typical measurement error was less than the a priori thresholds of clinical interest, and we found minimal evidence of systematic test-retest error. We found strong evidence of content validity, convergent construct validity with the Short-Form 12 Version 2 HRQL instrument, and feasibility of administration in an elite, competitive athletic population. CONCLUSIONS: These data suggest that the TLC Health Survey is a valid and reliable instrument for assessing lifetime and recent health, exercise, and HRQL, among elite competitive athletes. Generalizability of the instrument may be enhanced by additional, larger-scale studies in diverse populations.


Asunto(s)
Atletas , Ejercicio Físico/fisiología , Estado de Salud , Encuestas Epidemiológicas/normas , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Psicometría , Reproducibilidad de los Resultados , Autoinforme , Encuestas y Cuestionarios/normas , Universidades , Adulto Joven
17.
Sports Health ; 7(1): 80-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25553217

RESUMEN

BACKGROUND: Despite prominent public attention, data on life span health and exercise outcomes among elite, competitive athletes are sparse and do not reflect the diversity of modern athletes. HYPOTHESIS: Life span exercise behavior differs between National Collegiate Athletic Association (NCAA) student athletes and a nonathlete control group. Sustained exercise is associated with improved cardiopulmonary health outcomes. STUDY DESIGN: Cross-sectional, descriptive epidemiology study. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 496 students and alumni (age range, 17-84 year) at a large, NCAA Division I university, including student athletes and an age- and sex-matched nonathlete control group, completed anonymous, self-report health and exercise questionnaires. Age-stratified, cross-sectional analysis evaluated previous week's total exercise volume (ExVol), self-rated exercise importance (ExImp), and compliance with American College of Sports Medicine (ACSM) exercise guidelines for healthy adults. The association of ACSM guideline compliance with lifetime cardiopulmonary health outcomes was also assessed. RESULTS: Current student athletes reported significantly greater ExVol (P < 0.001. Cohen d = 0.99, probability of clinically important difference [pCID] >99.5%), ExImp (P < 0.001, d = 1.96, pCID = 96%), and likelihood of compliance with ACSM guidelines (odds ratio [OR], 95% confidence interval [CI] = 30.6, 11.0-84.6) compared with nonathletes. No significant differences were found between alumni student athletes and nonathletes. Alumni student athletes demonstrated substantially lower ExVol (P < 0.001, d = -0.94, pCID >99.5%) and guideline compliance (OR = 0.09, 95% CI = 0.05-0.19) compared with current student athletes, whereas nonathletes had similar exercise behavior across the life span. Among alumni, ACSM guideline compliance was associated with significant attenuation of cardiopulmonary health concerns (P = 0.02, d = -0.50, pCID = 14%) independent of intercollegiate athletic participation. CONCLUSION: Although current NCAA Division I student athletes demonstrated significant, clinically important differences in exercise behavior compared with nonathletes, no group differences were evident later in life. Irrespective of collegiate athletic status, healthy exercise behavior among alumni was associated with cardiopulmonary health benefits. CLINICAL RELEVANCE: To realize life span health benefits, it is imperative that student athletes maintain consistent patterns of healthy exercise beyond retirement from competitive sports.

18.
Eur J Appl Physiol ; 115(2): 295-308, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25294666

RESUMEN

PURPOSE: To determine if 8 weeks of periodized strength resistance training (RT) utilizing relatively short rest interval lengths (RI) in between sets (SS) would induce greater improvements in body composition and muscular performance, compared to the same RT program utilizing extended RI (SL). METHODS: 22 male volunteers (SS: n = 11, 65.6 ± 3.4 years; SL: n = 11, 70.3 ± 4.9 years) were assigned to one of two strength RT groups, following 4 weeks of periodized hypertrophic RT (PHRT): strength RT with 60-s RI (SS) or strength RT with 4-min RI (SL). Prior to randomization, all 22 study participants trained 3 days/week, for 4 weeks, targeting hypertrophy; from week 4 to week 12, SS and SL followed the same periodized strength RT program for 8 weeks, with RI the only difference in their RT prescription. RESULTS: Following PHRT, all study participants experienced increases in lean body mass (LBM) (p < 0.01), upper and lower body strength (p < 0.001), and dynamic power (p < 0.001), as well as decreases in percentage body fat (p < 0.05). Across the 8-week strength RT phase, SS experienced significantly greater increases in LBM (p = 0.001), flat machine bench press 1-RM (p < 0.001), bilateral leg press 1-RM (p < 0.001), narrow/neutral grip lat pulldown (p < 0.01), and Margaria stair-climbing power (p < 0.001), compared to SL. CONCLUSIONS: This study suggests 8 weeks of periodized high-intensity strength RT with shortened RI induces significantly greater enhancements in body composition, muscular performance, and functional performance, compared to the same RT prescription with extended RI, in older men. Applied professionals may optimize certain RT-induced adaptations, by incorporating shortened RI.


Asunto(s)
Composición Corporal , Entrenamiento de Fuerza/métodos , Sarcopenia/terapia , Anciano , Rendimiento Atlético , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/fisiología
19.
BMC Surg ; 14: 102, 2014 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-25481088

RESUMEN

BACKGROUND: The anterior cruciate ligament (ACL) is one of four major ligaments in the knee that provide stability during physical activity. A tear in the ACL is characterized by joint instability that leads to decreased activity, knee dysfunction, reduced quality of life and a loss of muscle mass and strength. While rehabilitation is the standard-of-care for return to daily function, additional surgical reconstruction can provide individuals with an opportunity to return to sports and strenuous physical activity. Over 200,000 ACL reconstructions are performed in the United States each year, and rehabilitation following surgery is slow and expensive. One possible method to improve the recovery process is the use of intramuscular testosterone, which has been shown to increase muscle mass and strength independent of exercise. With short-term use of supraphysiologic doses of testosterone, we hope to reduce loss of muscle mass and strength and minimize loss of physical function following ACL reconstruction compared to standard-of-care alone. METHODS/DESIGN: This study is a double-blinded randomized control trial. Men 18-50 years of age, scheduled for ACL reconstruction are randomized into two groups. Participants randomized to the testosterone group receive intramuscular testosterone administration once per week for 8 weeks starting 2 weeks prior to surgery. Participants randomized to the control group receive a saline placebo intramuscularly instead of testosterone. Lean mass, muscle strength and physical function are measured at 5 time points: 2 weeks pre-surgery, 1 day pre-surgery, and 6, 12, 24 weeks post-surgery. Both groups follow standard-of-care rehabilitation protocol. DISCUSSION: We believe that testosterone therapy will help reduce the loss of muscle mass and strength experienced after ACL injury and reconstruction. Hopefully this will provide a way to shorten the rehabilitation necessary following ACL reconstruction. If successful, testosterone therapy may also be used for other injuries involving trauma and muscle atrophy. TRIAL REGISTRATION: NCT01595581, REGISTRATION: May 8, 2012.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Testosterona/administración & dosificación , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior/rehabilitación , Método Doble Ciego , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Periodo Perioperatorio , Recuperación de la Función , Adulto Joven
20.
J Athl Train ; 49(5): 684-95, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25117874

RESUMEN

CONTEXT: Competitive sports are recognized as having unique health benefits and risks, and the effect of sports on life-span health among elite athletes has received increasing attention. However, supporting scientific data are sparse and do not represent modern athletes. OBJECTIVE: To assess holistic life-span health and health-related quality-of-life (HRQL) among current and former National Collegiate Athletic Association student-athletes (SAs). DESIGN: Cross-sectional study. SETTING: A large Division I university. PATIENTS OR OTHER PARTICIPANTS: Population-based sample of 496 university students and alumni (age 17-84 years), including SAs and an age-matched and sex-matched nonathlete (NA) control group. MAIN OUTCOME MEASURE(S): Participants completed anonymous, self-report questionnaires. We measured the Short-Form 12 (SF-12) physical and mental component HRQL scores and cumulative lifetime experience and relative risk of treatment for joint, cardiopulmonary, and psychosocial health concerns. RESULTS: Older alumni (age 43+ years) SAs reported greater joint health concerns than NAs (larger joint summary scores; P = .04; Cohen d = 0.69; probability of clinically important difference [pCID] = 77%; treatment odds ratio [OR] = 14.0, 95% confidence interval [CI] = 1.6, 126). Joint health for current and younger alumni SAs was similar to that for NAs. Older alumni reported greater cardiopulmonary health concerns than younger alumni (summary score P < .001; d = 1.05; pCID = 85%; OR = 5.8, 95% CI = 2.0, 16) and current students (P < .001; d = 2.25; pCID >99.5%; OR = 7.1, 95% CI = 3.3, 15), but the risk was similar for SAs and NAs. Current SAs demonstrated evidence of better psychosocial health (summary score P = .006; d = -0.52; pCID = 40%) and mental component HRQL (P = .008; d = 0.50; pCID = 48%) versus NAs but similar psychosocial treatment odds (OR = 0.87, 95% CI = 0.39, 1.9). Psychosocial health and mental component HRQL were similar between alumni SAs and NAs. No differences were observed between SAs and NAs in physical component HRQL. CONCLUSIONS: The SAs demonstrated significant, clinically meaningful evidence of greater joint health concerns later in life, comparable cardiopulmonary health, and differences in life-span psychosocial health and HRQL profiles compared with NAs. These data provide timely evidence regarding a compelling public issue and highlight the need for further study of life-span health among modern athletes.


Asunto(s)
Atletas , Traumatismos en Atletas/psicología , Salud Mental , Calidad de Vida , Estudiantes , Universidades , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Traumatismos en Atletas/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Adulto Joven
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