Does exercise intensity increment in exergame promote changes in strength, functional capacity and perceptual parameters in pre-frail older women? A randomized controlled trial.

The aim of this study was to compare the effects of two exercise intensities on exergame training program in muscle strength, functional capacity and perceptual parameters in pre-frail older women. Thirty-four women (69.5 ±â€¯5.4 years) were randomly assigned to either moderate- (MG: 11-13 perceived exertion) or vigorous-exercise intensity group (VG: 14-16 perceived exertion). Muscle strength and functional capacity were evaluated before and after 3 months of training. The affective responses were measured once a week and perceived benefit was evaluated after training period. The MG improved the average power at 60°/s from pre- to post-training (p < 0.002) on the knee extensor (pre = 100.0 ±â€¯15.9 W; post = 115.2 ±â€¯22.6 W), flexor (pre = 22.3 ±â€¯6.1 W; post = 29.1 ±â€¯7.9 W) and plantiflexor muscles (pre = 11.4 ±â€¯5.9 W; post = 21.2 ±â€¯4.2 W). MG presented greater average power at post-training than VG for knee extensor (20%) and flexor muscles (23%) (p < 0.039). There was main time effect of peak torque at 180°/s for knee extensor (pre = 74.15 ±â€¯14.28 N·m/kg; post = 81.31 ±â€¯18.4 N·m/kg), flexor (pre = 43.01 ±â€¯12.43 N·m/kg; post = 48.3 ±â€¯9.11 N·m/kg) and plantiflexor muscles (pre = 29.2 ±â€¯13.76 N·m/kg; post = 36.87 ±â€¯9.7 N·m/kg) as well as average power (pre = 41.15 ±â€¯15.67 W; post = 48.42 ±â€¯11.8 W) and work (pre = 99.92 ±â€¯38.53 J; post = 117.03 ±â€¯25.56 J) on the knee flexor muscles (p < 0.046). MG improved timed up and go performance from pre- to post-training (pre = 10.0 ±â€¯0.32 s; post = 8.1 ±â€¯1.6 s, p = 0.001), whereas both groups improved 10 m-walk performance (pre = 1.33 ±â€¯0.25 s, post = 1.5 ±â€¯0.24 s; p = 0.003). Positive affect (2.64 ±â€¯0.02) and pleasure (15.8 ±â€¯0.6) for MG were greater than VG at post-training (2.36 ±â€¯0.03; p < 0.001; 14.4 ±â€¯0.5; p < 0.03). Therefore, regardless of the exercise intensity, exergame training improved muscle strength and functional capacity in pre-frail older women. However, positive affect and pleasure were reported only when older women practiced exergame with moderate exercise intensity.

The effects of a water-based exercise program on strength and functionality of older adults.

OBJECTIVE: To analyze the effects of a water-based exercise program on peak torque (PT) and rate of torque development (RTD) during maximal voluntary ballistic isometric contractions of the lower limb muscles and the performance of a number of functional tests in the elderly. METHOD: Thirty-seven elderly were randomly assigned to water-based training (3 d/wk for 12 wk) or a control group. Extensor and flexor PT and RTD of the ankle, knee, and hip joints and functional tests were evaluated before and after training. RESULTS: PT increased after training for the hip flexors (18%) and extensors (40%) and the plantar-flexor (42%) muscles in the water-based group. RTD increased after training for the hip-extensor (10%), knee-extensor (11%), and ankle plantar-flexor (27%) muscles in the water-based group. Functional tests also improved after training in the water-based group (p < .05). CONCLUSION: The water-based program improved PT and RTD and functional performance in the elderly.

Effects of strength and power training on neuromuscular variables in older adults.

The purpose of this study was to compare the neuromuscular adaptations produced by strength-training (ST) and power-training (PT) regimens in older individuals. Participants were balanced by quadriceps cross-sectional area (CSA) and leg-press 1-repetition maximum and randomly assigned to an ST group (n = 14; 63.6 ± 4.0 yr, 79.7 ± 17.2 kg, and 163.9 ± 9.8 cm), a PT group (n = 16; 64.9 ± 3.9 yr, 63.9 ± 11.9 kg, and 157.4 ± 7.7 cm), or a control group (n = 13; 63.0 ± 4.0 yr, 67.2 ± 10.8 kg, and 159.8 ± 6.8 cm). ST and PT were equally effective in increasing (a) maximum dynamic and isometric strength (p < .05), (b) increasing quadriceps muscle CSA (p < .05), and (c) decreasing electrical mechanical delay of the vastus lateralis muscle (p < .05). There were no significant changes in neuromuscular activation after training. The novel finding of the current study is that PT seems to be an attractive alternative to regular ST to maintain and improve muscle mass.

The effects of stretching on the flexibility, muscle performance and functionality of institutionalized older women.

Stretching has been widely used to increase the range of motion. We assessed the effects of a stretching program on muscle-tendon length, flexibility, torque, and activities of daily living of institutionalized older women. Inclusion/exclusion criteria were according to Mini-Mental State Examination (MMSE) (>13), Barthel Index (>13) and Lysholm Scoring Scale (>84). Seventeen 67 ± 9 year-old elderly women from a nursing home were divided into 2 groups at random: the control group (CG, N = 9) participated in enjoyable cultural activities; the stretching group (SG, N = 8) performed active stretching of hamstrings, 4 bouts of 1 min each. Both groups were supervised three times per week over a period of 8 weeks. Peak torque was assessed by an isokinetic method. Both groups were evaluated by a photogrammetric method to assess muscle-tendon length of uni- and biarticular hip flexors and hamstring flexibility. All measurements were analyzed before and after 8 weeks by two-way ANOVA with the level of significance set at 5%. Hamstring flexibility increased by 30% in the SG group compared to pre-training (76.5 ± 13.0° vs 59.5 ± 9.0°, P = 0.0002) and by 9.2% compared to the CG group (76.5 ± 13.0° vs 64.0 ± 12.0°, P = 0.0018). Muscle-tendon lengths of hip biarticular flexor muscles (124 ± 6.8° vs 118.3 ± 7.6°, 5.0 ± 7.0%, P = 0.031) and eccentric knee extensor peak torque were decreased in the CG group compared to pre-test values (-49.4 ± 16.8 vs -60.5 ± 18.9 Nm, -15.7 ± 20%, P = 0.048). The stretching program was sufficient to increase hamstring flexibility and a lack of stretching can cause reduction of muscle performance.

The effects of stretching on the flexibility, muscle performance and functionality of institutionalized older women

Stretching has been widely used to increase the range of motion. We assessed the effects of a stretching program on muscle-tendon length, flexibility, torque, and activities of daily living of institutionalized older women. Inclusion/exclusion criteria were according to Mini-Mental State Examination (MMSE) (>13), Barthel Index (>13) and Lysholm Scoring Scale (>84). Seventeen 67 ± 9 year-old elderly women from a nursing home were divided into 2 groups at random: the control group (CG, N = 9) participated in enjoyable cultural activities; the stretching group (SG, N = 8) performed active stretching of hamstrings, 4 bouts of 1 min each. Both groups were supervised three times per week over a period of 8 weeks. Peak torque was assessed by an isokinetic method. Both groups were evaluated by a photogrammetric method to assess muscle-tendon length of uni- and biarticular hip flexors and hamstring flexibility. All measurements were analyzed before and after 8 weeks by two-way ANOVA with the level of significance set at 5 percent. Hamstring flexibility increased by 30 percent in the SG group compared to pre-training (76.5 ± 13.0° vs 59.5 ± 9.0°, P = 0.0002) and by 9.2 percent compared to the CG group (76.5 ± 13.0° vs 64.0 ± 12.0°, P = 0.0018). Muscle-tendon lengths of hip biarticular flexor muscles (124 ± 6.8° vs 118.3 ± 7.6°, 5.0 ± 7.0 percent, P = 0.031) and eccentric knee extensor peak torque were decreased in the CG group compared to pre-test values (-49.4 ± 16.8 vs -60.5 ± 18.9 Nm, -15.7 ± 20 percent, P = 0.048). The stretching program was sufficient to increase hamstring flexibility and a lack of stretching can cause reduction of muscle performance.

Changes in stature during and after spinal traction in young male subjects

BACKGROUND: Spinal traction is a relatively popular procedure for increasing the intervertebral space by applying separating forces. The parameters of time and magnitude of the traction forces may influence the outcomes from this procedure and need to be investigated. The duration of the benefits derived from traction is unknown and needs to be determined so that physiotherapists can provide better and more effective treatments. OBJECTIVE: This study analyzed the relationship between load magnitude and time during spinal traction in relation to stature variations. Traction effect duration was also analyzed. METHOD: Fifteen healthy male subjects (23.1 ± 5.77 years; 1.80 ± 0.17 m and 87.0 ± 9.6 kg) were assessed under three traction conditions (0, 30 and 60 percent of body weight, BW) of 42 minutes. Stature variation was used to determine intervertebral disc height variation. Stature was assessed every 7 minutes during traction of 42 minutes and every 5 minutes for 45 minutes after traction ceased. RESULTS: 0 and 30 percent BW traction produced similar gains (6.09 ± 1.89 mm, 5.70 ± 1.88 mm, respectively; p>0.05), while these were smaller (p<0.05) than at 60 percent BW (7.01 ± 1.98 mm). Significant differences (p<0.05) between 60 percent BW and the other conditions occurred only after the 21st minute. Stature loss after traction showed that the traction effects were transient and lasted for approximately one hour. This suggests that traction loads of 30 percent BW are insufficient to produce stature gains similar to those observed with 60 percent BW. CONCLUSION: Traction showed a short-duration transient effect. For this effect to be maintained, it must be repeated at one-hour intervals. Its use is questioned because of its transient nature.

CONTEXTUALIZAÇÃO: A tração sobre a coluna vertebral é um procedimento relativamente popular para aumentar o espaço inter-vertebral pela aplicação de forças de separação. Os parâmetros de tempo e magnitude da força aplicada podem influenciar os resultados desse procedimento e ainda precisam ser investigados. A duração dos benefícios derivados da tração não é conhecida e precisa ser determinada para que fisioterapeutas possam prover tratamentos melhores e mais eficientes. OBJETIVO: Este estudo analisou a relação entre a magnitude de carga e de tempo durante a tração vertebral sobre as variações de estatura, bem como a duração deste efeito. MÉTODOS: Quinze sujeitos saudáveis do sexo masculino (23,1 ± 5,77 anos; 1,80 ± 0,17 m e 87,0 ± 9,6 Kg) foram mensurados sob três condições (0, 30 e 60 por cento PC) de 42 minutos. A variação de estatura foi utilizada para determinar a variação da altura dos discos intervertebrais. A estatura foi verificada a cada 7 min durante a tração de 42 min e a cada 5 min por 45 min após o término da tração. RESULTADOS: A tração com 0 e 30 por cento do PC produziu ganhos similares (6,09 ± 1,89mm, 5,70 ± 1,88mm, respectivamente; p>0,05), que foram menores (p<0,05) que com 60 por cento do PC (7,01 ± 1,98 mm). Diferenças significativas (p<0,05) entre 60 por cento do PC e outras condições ocorreram apenas após o 21º min. A perda de estatura após a tração demonstrou que os efeitos da tração vertebral são transientes e duram aproximadamente 1 hora. Isso sugere que a carga de tração de 30 por cento PC não é suficiente para produzir ganhos de estatura similares aos observados com 60 por cento PC. CONCLUSÃO: A tração demonstrou um efeito transiente e de curta duração, para esse efeito ser mantido ele deve ser repetido em intervalos de 1 hora. O uso da tração é questionado devido ao seu efeito transiente.

Changes in stature and spine kinematics during a loaded walking task.

The aim of the present study was to quantify the kinematics of the spine and stature loss induced by the asymmetric load carriage. Six healthy males with no history of low-back disorders walked at their self-selected pace for 8,500 m with and without a standard Royal Mail bag (model MB36) containing 17.5% of the participant's body mass. The load was reduced gradually during the task. The loaded condition produced a stature loss double that observed in the unloaded condition. Increased forward leaning (up to 6 degrees ) and lateral bending of the spine (up to 12 degrees ) was observed with load. Thoracic adjustments occurred in the sagittal plane, changes in the lumbar area occurred in the frontal plane. The data provided evidence against mailbags designs in which the workers cannot alternate the side of the mailbag.

Diferenças entre medidas quali e quantitativas durante testes de comprimento musculo-tendineos dos flexores do quadril uni e biarticulares / Difference between qualitative and quantitative measurements during muscle-tendon length tests on the uni-and biarticular hip flexors

am objetivo deste estudo foi determinar a concordancia entre avaliadores nas medidas de analise subjetiva de comprimento musculo-tendineo dos flexores uni e biarticulares do quadril durante a realizacao do teste de Thomas. Este estudo tambem objetivou comparar o diagnostico qualitativo em relacao ao diagnostico quantitativo fotografico e testar a reprodutibilidade do metodo fotografico. Metodos: foram fotografados 15 sujeitos nas posicoes inicial e final do teste de Thomas. Imediatamente pos o teste, os sujeitos foram novamente fotografados mais duas vezes, a fim de gerar5 tres conjuntos de dados. Dessa forma, um total de 90 fotografias foram obtidas para a determinacao da reprodutibilidade do teste. Um conjunto de 30 fotografias (15 em posicao inicial e 15 em posicao final) foram selecionadas aleatoriamente e apresentadas a 16 avaliadores experientes. Resultados: foi observada baixa concordancia entre avaliadores nas avaliacoes subjetivas para comprimento musculo-tendineo dos flexores uni e biarticulares do quadril. A analise da avaliacao subjetiva demosntrou problemas para diferenciar individuos com comprimento musculo-tendineo normal daqueles com leve encurtamento (p<0,05). Em contrapartida, a avaliacao objetiva demonstrou alta reprodutibilidade entre as sessoes (a=0,96) e baixo erro absoluto (0,72 grau) para os flexores uniarticulares do quadril. Os flexores biarticulares do quadril tambem demonstraram alta reprodutibilidade (a=0,95) e baixo erro absoluto (1,4 grau). Conclusoes: sugere-se que os procedimentos objetivos sejam preferidos para a determinacao do comprimento musculo-tendineo dos flexores uni e biarticulares do quadril no teste de Thomas pela alta reproditibilidade e baixo erro de medidas apresentados com comparacao as abordagens subjetivas

Multi-segment coordination: fatigue effects.

PURPOSE: The aim of this study was to investigate the segmental coordination of vertical jumps under fatigue. METHODS: Twelve subjects performed maximal countermovement jumps with and without fatigue, which was imposed by maximal continuous jumps in place until their maximal jump height corresponded to 70% of the nonfatigued condition. Video, ground reaction forces, and electromyographic signals were recorded to analyze the segmental coordination of countermovement jumps before (CMJ1) and after (CMJ2) fatigue. The magnitude of joint extension initiation, peak joint angular velocity, and peak net power around the ankle, knee, and hip joints and their respective times were determined. RESULTS: CMJ2 was characterized by a longer contact time, which was accompanied with an earlier movement initiation and several differences (P < 0.05) in the variables used to describe coordination. When the movement duration was normalized with respect to the contact phase duration, the differences between CMJ1 and CMJ2 were not sustained. A consistent pattern was indicated, in which the segmental coordination did not differ between jump conditions. When the magnitude of the muscle activation was set aside, a remarkably consistent muscle activation time was noticed between conditions. CONCLUSIONS: It was indicated that countermovement jumps were performed with a consistent well-timed motion of the segments. A "common drive," which acts without the knowledge of the muscle properties, was suggested as mediating and controlling the muscle activation timing between agonist-antagonist muscle pairs.

Intermuscular coordination during pendulum rebound exercises.

In this study, we assessed coordination during pendulum rebound jumps. To gain insight into the movement coordination strategy, nine experienced male volleyball players performed maximal rebound jumps in a pendulum swing device using three different seat arrangements (90 degrees, 135 degrees and 180 degrees). Two-dimensional filming was performed in the right sagittal plane (200 Hz) synchronized with a force platform fitted to the wall (1000 Hz). The surface electromyograms of five muscles were recorded (200 Hz), in conjunction with kinematic and kinetic assessment. During the countermovement phase, the impact forces were attenuated by eccentric contractions of most muscles, which helped to reduce the energy input into the system. The wall reaction forces, net moments and joint power profiles were comparable between conditions. The small differences found between the extreme seat arrangements were attributed to differences in muscle length and the position of the feet. The strategy used during landing was similar to that observed in unconstrained vertical and drop jumps, where the neuromuscular system attenuates the impact forces. During the push-off phase, most muscles were found to contribute to positive work generation, except the semitendinosus, which was stretching throughout the propulsive phase. Despite not being able to exert a large influence over the trunk segment, this muscle was deemed to play an important role in regulating and synchronizing the onset of knee extension, enabling hip extension to occur before extension in the other more distal joints. Our findings show that the neuromuscular system is able to produce consistent movement coordination across experimental conditions and in accordance with the specific task demands and constraints imposed in the movement structure.

Technical note: repeatability of measurement in determining stature in sitting and standing postures.

The aim of this study was to determine the effect of sitting and standing postures on the repeatability of a stadiometer designed to detect small variations in spinal length. Two groups of ten healthy subjects, with no previous or known history of back problems, participated in this study. One group was measured in the standing posture, while the other group was measured in a sitting posture. All subjects gave informed consent to participate in this study. Subjects had a set of landmarks defining the spinal contour marked on their backs and then stood in the stadiometer for three series of ten measurements to be performed. At the end of each measurement, the subjects were requested to move away from and then be repositioned in the stadiometer. Subjects improved the repeatability across the measurement series. At the end of the second measurement series, all subjects presented mean standard deviations of 0.43 +/- 0.08 mm (range 0.30-0.50 mm) in the standing posture. In the sitting posture, deviations of less than 0.05 mm were obtained only at the end of the third measurement series (0.48 +/- 0.08 mm; range 0.34-0.62 mm), suggesting that this posture required three measurement series before repeatable measurements could be assured rather than two in the standing posture.