Inter-limb differences in parameters of aerobic function and local profiles of deoxygenation during double-leg and counterweighted single-leg cycling

It is typically assumed that in the context of double-leg cycling, dominant ($DOM_L$$_E$$_G$) and non-dominant ($NDOM_L$$_E$$_G$) legs have similar aerobic capacity and that both contribute equally to the whole-body physiological responses. However, there is a paucity of studies that have systematically investigated maximal and submaximal aerobic performance and characterized the profiles of local muscle deoxygenation in relation to leg-dominance. Using counterweighted single-leg cycling, this study explored whether peak $O_2$ consumption ($V̇O_2$$_p$$_e$$_a$$_k$), maximal lactate steady-state ($MLSS_p$), and profiles of local deoxygenation [HHb] would be different in the $DOM_L$$_E$$_G$ compared with the $NDOM_L$$_E$$_G$. Twelve participants performed a series of double-leg and counterweighted single-leg $DOM_L$$_E$$_G$ and $NDOM_L$$_E$$_G$$i)$ ramp-exercise tests, and $ii)$ 30-min constant-load trials. $V̇O_2$$_p$$_e$$_a$$_k$ was greater in the $DOM_L$$_E$$_G$ than in the $NDOM_L$$_E$$_G$ (2.87±0.42 vs 2.70±0.39 L·min-1; P<0.05). The difference in $V̇O_2$$_p$$_e$$_a$$_k$ persisted even after accounting for lean mass (P<0.05). Similarly, $MLSS_p$ was greater in the $DOM_L$$_E$$_G$ than in the $NDOM_L$$_E$$_G$ (118±31 vs 109±31 W; P<0.05). Furthermore, the amplitude of the [HHb] signal during ramp-exercise was larger in the $DOM_L$$_E$$_G$ than in the $NDOM_L$$_E$$_G$ during both double-leg (26.0±8.4 vs 20.2±8.8 µM; P<0.05) and counterweighted single-leg cycling (18.5±7.9 vs 14.9±7.5 µM; P<0.05). Additionally, the amplitudes of the [HHb] signal were highly-to-moderately correlated with the mode-specific $V̇O_2$$_p$$_e$$_a$$_k$ values (ranging from 0.91 to 0.54). These findings showed, in a group of young men, that maximal and submaximal aerobic capacities were greater in the $DOM_L$$_E$$_G$ than in the $NDOM_L$$_E$$_G$, and that superior peripheral adaptations of $DOM_L$$_E$$_G$ may underpin these differences

Effect of Saddle height on skin temperature measured in different days of cycling.

Infrared thermography can be useful to explore the effects of exercise on neuromuscular function. During cycling, it could be used to investigate the effects of saddle height on thermoregulation. The aim of this study was to examine whether different cycling postures, elicited by different knee flexion angles, could influence skin temperature. Furthermore, we also determined whether the reproducibility of thermal measurements in response to cycling differed in the body regions affected or not affected by saddle height. Sixteen cyclists participated in three tests of 45 min of cycling at their individual 50 % peak power output. Each test was performed in a different knee flexion position on the bicycle (20°, 30°, 40° knee flexion when the pedal crank was at 180°). Different knee angles were obtained by changing saddle height. Skin temperatures were determined by infrared thermography before, immediately after and 10 min after the cycling test, in 16 different regions of interest (ROI) in the trunk and lower limbs. Changes in saddle height did not result in changes in skin temperature in the ROI. However, lower knee flexion elicited higher temperature in popliteus after cycling than higher flexion (p = 0.008 and ES = 0.8), and higher knee flexion elicited lower temperature variation in the tibialis anterior than intermediate knee flexion (p = 0.004 and ES = 0.8). Absolute temperatures obtained good and very good intraday reproducibility in the different measurements (ICCs between 0.44 and 0.85), but temperature variations showed lower reproducibility (ICCs between 0.11 and 0.74). Different postures assumed by the cyclist due to different saddle height did not influence temperature measurements. Skin temperature can be measured on different days with good repeatability, but temperature variations can be more sensitive to the effects of an intervention

Avaliação da qualidade de vida com o instrumento SF-36 em lombalgia crônica

OBJETIVO: Avaliar a qualidade de vida através dos domínios do Instrumento SF-36 em portadores de lombalgia crônica inespecífica. MÉTODOS: Trinta portadores de lombalgia crônica inespecífica foram aleatorizados para três grupos (grupo Iso (Isostretching), grupo RPG (Reeducação Postural Global) e Iso+RPG), e avaliados quanto à dor e qualidade de vida antes e após as intervenções fisioterápicas e reavaliados novamente após 2 meses de acompanhamento. Após a aceitação do Termo de Consentimento Livre e Esclarecido os pacientes foram submetidos a procedimentos como: avaliação fisioterápica através do Instrumento de Avaliação da Coluna Vertebral, Escala Visual Analógica de Dor (EVA), Questionário de Qualidade de Vida através do Instrumento SF-36, antes da 1ª sessão e após três meses de tratamento, e reavaliados 2 meses após o tratamento. RESULTADOS: Mostraram que ambas as técnicas fisioterápicas diminuíram a dor (p<0,001), porém quando foram associadas as duas técnicas (Iso + RPG) a melhora da dor foi significativamente maior, e na avaliação após dois meses de acompanhamento o método de RPG foi mais eficaz. Quanto à avaliação da qualidade de vida, as técnicas fisioterápicas foram eficazes após as intervenções (P<0,001), porém o método do Iso foi mais eficaz quando os pacientes foram reavaliados no acompanhamento. CONCLUSÃO: As técnicas fisioterápicas utilizadas neste estudo foram eficazes para tratar a lombalgia crônica inespecífica apresentada pelos pacientes, pois diminuíram a algia que os mesmos apresentavam e melhoraram a qualidade de vida segundo os domínios do Instrumento SF-36. Nível de Evidência II, Ensaio Clínico Controlado e Randomizado. ____________________________________________________________________________________ ABSTRACTThe objective of this study was to evaluate the quality of life (QL) with the use of the SF-36 Questionnaire in patients with chronic nonspecific low back pain (CNLBP). Thirty patients with CNLBP were randomly assigned to one of three groups (Iso group (Isostretching), GPR group (Global Postural Reeducation), and the Iso+GPR group. Patients underwent physical therapy assessment with the use of the Vertebral Spine Assessment, the Visual Analog Scale of Pain (VASP), and the SF-36 life quality questionnaire before the first session (first assessment), after three months of treatment (second assessment) and reassessed two months after the final session in the follow-up (third assessment). The results indicated that both physical therapy techniques reduced pain (p<0.001); when the techniques (Iso+GPR) were combined, the reduction in pain was significantly greater; and, in the follow-up assessment, the GPR method was more efficient. As for the QL, physical therapy techniques were effective after the interventions (p<0.001), and the Iso method was more effective when patients were reassessed in the follow-up. We conclude that the physical therapy techniques used in this study were efficient to treat CNLBP in the patients since they reduced pain and increased QL according to the results of the SF-36 questionnaire. Level of Evidence II, Randomized Controlled Clinical Trial