Armando Raimundo

Low-frequency vibratory exercise reduces the risk of bone fracture more than walking: a randomized controlled trial

BackgroundWhole-body vibration (WBV) is a new type of exercise that has been increasingly tested for the ability to prevent bone fractures and osteoporosis in frail people. There are two currently marketed vibrating plates: a) the whole plate oscillates up and down; b) reciprocating vertical displacements on the left and right side of a fulcrum, increasing the lateral accelerations. A few studies have shown recently the effectiveness of the up-and-down plate for increasing Bone Mineral Density (BMD) and balance; but the effectiveness of the reciprocating plate technique remains mainly unknown. The aim was to compare the effects of WBV using a reciprocating platform at frequencies lower than 20 Hz and a walking-based exercise programme on BMD and balance in post-menopausal women.MethodsTwenty-eight physically untrained post-menopausal women were assigned at random to a WBV group or a Walking group. Both experimental programmes consisted of 3 sessions per week for 8 months. Each vibratory session included 6 bouts of 1 min (12.6 Hz in frequency and 3 cm in amplitude with 60° of knee flexion) with 1 min rest between bouts. Each walking session was 55 minutes of walking and 5 minutes of stretching. Hip and lumbar BMD (g·cm-2) were measured using dual-energy X-ray absorptiometry and balance was assessed by the blind flamingo test. ANOVA for repeated measurements was adjusted by baseline data, weight and age.ResultsAfter 8 months, BMD at the femoral neck in the WBV group was increased by 4.3% (P = 0.011) compared to the Walking group. In contrast, the BMD at the lumbar spine was unaltered in both groups. Balance was improved in the WBV group (29%) but not in the Walking group.ConclusionThe 8-month course of vibratory exercise using a reciprocating plate is feasible and is more effective than walking to improve two major determinants of bone fractures: hip BMD and balance.

Prevalence of the Portuguese Population Attaining Sufficient Physical Activity

PURPOSEnPhysical activity has many health benefits, and to implement strategies, mainly in those groups with insufficient levels of practice, it is important to evaluate physical activity. The main purpose of this study was to describe the prevalence of physical activity in the Portuguese population aged 10 yr and older using accelerometry.nnnMETHODSnThe accelerometers were worn for four consecutive days, and a valid record was defined as at least 3 d with 10 h of wear time, including one weekend day. Considering these conditions, 4696 participants were included.nnnRESULTSnAccording to the recommendations of 60 min·d(-1) of physical activity, 36% of participants age 10-11 yr (boys = 51.6%, girls = 22.5%) and 4% age 16-17 yr (boys = 7.9%, girls = 1.2%) were considered sufficiently active. In adulthood, ∼70% of participants age 18-64 yr (men = 76.6%, women = 65.2%) and 35% age older than 64 yr (men = 46%, women = 29%) reached the recommendation of 30 min·d(-1) of physical activity, when counting every minute of moderate or greater intensity. Considering bouts of 10 min or more of moderate or greater intensity in participants older than 17 yr, the prevalence was 4%-6% at 18-39 yr, 7%-9% at 40-64 yr, and ∼3% in persons age 65 yr or older.nnnCONCLUSIONSnThe design and implementation of strategies to promote physical activity for health among children and adolescents and older adults, particularly girls/women, should be encouraged.

Prevalence of overweight and obesity among Portuguese youth: A study in a representative sample of 10–18-year-old children and adolescents

PURPOSEnThe aim of this research was to report the prevalence of overweight and obesity in a representative sample of Portuguese youth.nnnMETHODSnThis was a school-based study performed in Portugal. A total of 22 048 children and adolescents aged 10-18 years were included in the study. The World Health Organization (WHO) and the International Obesity Task Force (IOTF) cut-offs were used to categorise overweight and obese participants.nnnRESULTSnUsing IOTF cut-offs the prevalence of overweight and obesity was 17.0 and 4.6% in girls, and 17.7 and 5.8% in boys, respectively (p < 0.001 for overweight and p > 0.05 for obesity), whereas WHO cut-offs resulted in overweight and obesity prevalence scores of 23.1 and 9.6% in girls, and 20.4 and 10.3% in boys, respectively (p < 0.001 for overweight and p >0.05 for obesity). With IOTF cut-offs, a lower prevalence of obesity and overweight was observed at higher ages, in both genders. With the WHO cut-offs, a lower prevalence of obesity and overweight was observed at higher ages, in boys. In girls, the prevalence of overweight and obesity increases from 10 to 12 years of age and decreases from the age of 13 to 18 years.nnnCONCLUSIONnThe prevalence for overweight/obesity among Portuguese children and adolescents vary according to the cut-off points used and are also of concern requiring strategies to promote healthy weight gain among children and adolescents.

Prevalence of overweight, obesity, and abdominal obesity in a representative sample of Portuguese adults

This study determined the prevalence of overweight, obesity, and abdominal obesity in the Portuguese adults and examined the relationship between above mentioned prevalences and educational level. Body mass, stature, and waist circumference were measured in a representative sample of the Portuguese population aged 18–103 years (nu200a=u200a9,447; 18–64 years: nu200a=u200a6,908; ≥65 years: nu200a=u200a2,539). Overweight and obesity corresponded to a body mass index ranging between 25–29.9 kg/m2 and ≥30 kg/m2, respectively. Abdominal obesity was assessed as >102 cm for males and >88 cm for females. After adjusting for educational level, the combined prevalences of overweight and obesity were 66.6% in males and 57.9% in females (18–64 years). Respective values in older adults (≥65 years) were 70.4% for males and 74.7% for females. About 19.3% of adult males and 37.9% of adult females presented abdominal obesity. Correspondent values in older adults were 32.1%, for males, and 69.7%, for females. In adults, low educational level was related to an increased risk for overweight (ORu200a=u200a2.54; 95% CI: 2.08–3.09), obesity (ORu200a=u200a2.76; 95% CI: 2.20–3.45), and abdominal obesity (ORu200a=u200a5.48; 95% CI: 4.60–6.52). This reinforces the importance of adjusting public health strategies for educational level.

Improvements of muscle strength predicted benefits in HRQOL and postural balance in women with fibromyalgia: an 8-month randomized controlled trial

OBJECTIVEnTo evaluate whether changes in muscle strength due to 32 weeks of supervised aquatic training predicted improvements on health-related quality of life (HRQOL).nnnMETHODSnThirty women with FM aged 50.8 +/- 8.7 years were randomly assigned to an experimental group (n = 15), performing 3 weekly sessions of 60 min of warm-water exercise; or to a control group (n = 15). HRQOL was evaluated using the Short Form 36 Health Survey (SF-36). Maximal unilateral isokinetic strength was measured at 60 degrees/s and 210 degrees/s in the knee extensors and flexors in concentric action and at 60 degrees/s in knee extensors eccentric action. Postural balance was evaluated using the one-leg stance, eyes closed.nnnRESULTSnAfter 32 weeks of water exercise therapy, statistically significant improvements occurred in concentric knee flexors and extensors strength at 60 degrees/s, in eccentric knee extensors and in postural balance. The treatment led to additional improvements in physical function, role physical problems, body pain, general health, vitality, role emotional problems and mental health dimensions of SF-36. Gains in the concentric knee flexors strength predicted improvements in role of physical problems, whereas those in concentric knee extensors did the same for mental health and role emotional problems. Gains in eccentric knee extensors strength predicted improvements in postural balance.nnnCONCLUSIONSnA long-lasting exercise therapy in warm water produced relevant gains in muscle strength at low velocities of movements, some of which predicted improvements in physical problems, emotional problems, mental health and balance.nnnTRIAL REGISTRATIONnInternational Standard Randomized Controlled Trial Number ISRCTN53367487, information available in http://www.controlled-trials.com/ISRCTN53367487.

Fitness efficacy of vibratory exercise compared to walking in postmenopausal women.

In this study, we compared the efficacy of 8xa0months of low-frequency vibration and a walk-based program in health-related fitness. Twenty-seven postmenopausal women were randomly assigned into two groups: whole-body vibration (WBV) group (nxa0=xa018) performed three times/week a static exercise on a vibration platform (6 sets of 1-min with 1xa0min of rest, with a 12.6xa0Hz of frequency and an amplitude of 3xa0mm); walk-based program (WP) group (nxa0=xa018) performed three times/week a 60-min of walk activity at 70–75% of maximal heart rate. A health-related battery of tests was applied. Maximal unilateral concentric and eccentric isokinetic torque of the knee extensors was recorded by an isokinetic dynamometer. Physical fitness was measured using the following tests: vertical jump test, chair rise test and maximal walking speed test over 4xa0m. Maximal unilateral isokinetic strength was measured in the knee extensors in concentric actions at 60 and 300°/s, and eccentric action at 60°/s. After 8xa0months, the WP improved the time spent to walk 4 m (20%) and to perform the chair rise test (12%) compared to the WBV group (Pxa0=xa00.006, 0.002, respectively). In contrast, the comparison of the changes in vertical jump showed the higher effectiveness of the vibratory exercise in 7% (Pxa0=xa00.025). None of exercise programs showed change on isokinetic measurements. These results indicate that both programs differed in the main achievements and could be complementary to prevent lower limbs muscle strength decrease as we age [ISRCTN76235671].

Waist circumference percentiles for Portuguese children and adolescents aged 10 to 18 years

The purposes of this study were to develop age- and sex-specific waist circumference reference data for Portuguese children and adolescents aged 10–18xa0years and to compare them with those from other countries. This was a school-based study performed in Portugal. A total of 22,003 children and adolescents aged 10–18xa0years were included in the study. Smoothed sex- and age-specific 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentile curves of waist circumference were estimated using Coles lambda–mu–sigma method. Waist circumference values increased with age in both boys and girls, and boys had higher values than girls at every age and percentile. In both sexes, the Portuguese values in the 90th percentile were closer to the Bolivian values and considerably lower than those of the American children for all age groups. Conclusion: The data presented provide information for abdominal risk assessment and clinical and lifestyle intervention; our results also provide useful baseline data information for the implementation of a surveillance system required to monitor trends and factors associated with abdominal obesity in children and adolescents.

Shoulder rotator cuff balance, strength, and endurance in young swimmers during a competitive season.

Abstract Batalha, NM, Raimundo, AM, Tomas-Carus, P, Barbosa, TM, and Silva, AJ. Shoulder rotator cuff balance, strength, and endurance in young swimmers during a competitive season. J Strength Cond Res 27(9): 2562–2568, 2013—The purpose of this study was to analyze the effects of a competitive swim season on the strength, balance, and endurance of shoulder rotator cuff muscles in young swimmers. A repeated measures design was used with 3 measurements performed during the swim season. A swimmers group (n = 20) of young men with no dry land training and a sedentary group (n = 16) of male students with the same characteristics (age, body mass, height, and maturational state) were evaluated. In both groups, the peak torque of shoulder internal rotator (IRt) and external rotator (ERt) was assessed during preseason, midseason (16 weeks), and postseason (32 weeks). Concentric action at 60 and 180°·s−1 was measured using an isokinetic dynamometer. The ER/IR strength ratios and endurance ratios were also obtained. At 60°·s−1, there were significant training effects in the IRt strength and ER/IR ratio on both shoulders. This trend was the same throughout the competitive season. The same trend was present at 180°·s−1 because the training effects are seen primarily in IRt and ER/IR ratios. With respect to endurance ratios, within-group data were similar in ERt and IRt for both shoulders, with no significant differences between moments. However, between-group differences occurred mostly in the IRt. Results suggest that a competitive swim season favors the increase of muscular imbalances in the shoulder rotators of young competitive swimmers, mainly because of increased levels of IRt strength and endurance that are proportionally larger than those of their antagonists. A compensatory strength training program should be considered.

Urinary steroid profile after the completion of concentric and concentric/eccentric trials with the same total workload.

High intensity strength training causes changes in steroid hormone concentrations. This could be altered by the muscular contraction type: eccentric or concentric. The aim of this study was to compare the effect of the completion of a short concentric (CON) and concentric/eccentric (CON/ECC) trial on the urinary steroid profile, both with the same total work. 18 males performed the trials on an isokinetic dynamometer (BIODEX III) exercising quadriceps muscles, right and left, on different days. Trial 1(CON): 4×10 Concentric knee extension + relax knee flexion, speed 60°/second; rest 90 seconds between each series and 4 minutes between each leg exercise. Trial 2(CON/ECC): 4×5 concentric knee extension + Eccentric knee flexion under similar conditions. Urine samples were taken before the exercise and one hour after finishing it. Androsterone, Etiocholanolone, DHEA, Androstenedione, Testosterone, Epitestosterone, Dehydrotestosterone, Estrone, B-Estradiol, Tetrahydrocortisone, Tetrahydrocortisol, Cortisone and Cortisol (free, glucoconjugated and sulfoconjugated) urinary values were determined using gas chromatography/mass spectrometry techniques. No significant differences were noted in Total Work and Average Peak Torque, although Maximum Peak Torque in the CON/ECC trial was higher than in the CON trial. These results demonstrate no changes in the steroid profile before and after trials, or when comparing CON to CON/ECC trials. The data suggest that eccentric contractions do not cause hormonal changes different to the ones produced by concentric contractions, when they are performed in strength short trials with the same total workload.ResumenEl entrenamiento de fuerza de alta intensidad provoca variaciones en la concentración de esteroides. El tipo de contracción muscular, excéntrica o concéntrica, podría ser un factor que la alterase. El objetivo de este estudio fue comparar el efecto de la realización de una sesión corta de ejercicio concéntrico (CON) y otra concéntrica/excéntrica (CON/EXC), con la misma carga de trabajo total, sobre el perfil esteroideo urinario. 18 hombres realizaron dos sesiones de ejercicio de corta duración utilizando una máquina isocinética (BIODEX III) en días diferentes y trabajando los músculos cuádriceps de ambas piernas. La sesión de ejercicio 1 (CON) fue un 4×10 rep de extensión concéntrica de rodilla más relajación en el movimiento de flexión, a una velocidad de 60°/segundo y con una recuperación de 90 seg. entre cada serie y 4 minutos entre cada una de las piernas. La sesión de ejercicio 2 (CON/EXC) fue un 4×5 rep. de extensión concéntrica de rodilla más flexión excéntrica de rodilla, con las mismas condiciones de velocidad y recuperación. Muestras de orina fueron se tomaron antes del ejercicio y una hora después de finalizarlo. Los niveles urinarios (fracción libre, glucoconjugada y sulfoconjugada) de Androsterona, Etiocolanolona, DHEA, Androstenodiona, Testosterona, Epitestosterona, Dehidrotestosterona, Estrona, β-estradiol, Tetrahidrocortisona, Tetrahidrocortisol, Cortisona y Cortisol, se determinaron usando técnicas de cromatografía de gases-espectrometría de masas. No se encontraron diferencias significativas en los valores de Trabajo Total y de Pico Torque Medio, aunque los valores de Pico Torque Máximo fueron más alto en el CON/EXC ejercicio que en el CON. Tampoco se observó ningún cambio en el perfil esteroideo urinario entre antes y después de las sesiones de ejercicio, o comparando las sesiones CON/EXC con la CON. Por tanto, los datos sugieren que las contracciones excéntricas no producen alteraciones hormonales diferentes a las producidas por las contracciones concéntricas, cuando se trata de sesiones de ejercicio de fuerza de corta duración con similar carga de trabajo total.

Does an In-season Detraining Period Affect the Shoulder Rotator Cuff Strength and Balance of Young Swimmers?

Abstract Batalha, NM, Raimundo, AM, Tomas-Carus, P, Marques, MAC, and Silva, AJ. Does an in-season detraining period affect the shoulder rotator cuff strength and balance of young swimmers? J Strength Cond Res 28(7): 2054–2062, 2014—Imbalance in shoulder rotator muscles is a well-documented problem in swimmers, and it is important to implement land-based strength training programs. Meanwhile, the effects of a detraining period on swimmers shoulder rotator muscles are unknown. The purpose of this study was to analyze the effects of a strength training program and detraining on the strength and balance of shoulder rotator cuff muscles in young swimmers, despite the continuity of usual water training. An experimental group (n = 20) and a control group (n = 20) of young male swimmers with the same characteristics (age, body mass, height, training volume, and maturational state) were evaluated. In both groups, the peak torques of shoulder internal (IR) and external (ER) rotators were assessed during preseason, midseason (16 weeks), and postseason (32 weeks). The experimental group underwent a strength training regimen from baseline to 16 weeks and a detraining period from 16 to 32 weeks. Concentric action at 60°·s−1 and 180°·s−1 was measured using an isokinetic dynamometer. The ER/IR strength ratios were obtained. At 60°·s−1, there were significant increments in IR strength and the ER/IR ratio in both shoulders. This trend was the same throughout the competitive season. The tendency was the same at 180°·s−1 because training effects were noted primarily in IR and ER/IR ratios. Moreover, the absence of land-based strength training, from 16 to 32 weeks, revealed a reduction in the ER/IR ratio values in both shoulders. Our findings suggest that young swimmers coaches should use dry-land strength training protocols, and that it is recommended that these should be conducted on a regular basis (during the whole season).