A randomized controlled trial on the effects of combined aerobic-resistance exercise on muscle strength and fatigue, glycemic control and health-related quality of life of type 2 diabetes patients

Aim: to evaluate the effects of a 12-weeks combined aerobic-resistance exercise therapy on fatigue and isokinetic muscle strength, glycemic control and health-related quality of life (HRQoL) in moderately affected type 2 diabetes (T2DM) patients. Methods: a randomized controlled trial design was employed. Forty-three T2DM patients were assigned to an exercise group (n = 22), performing 3 weekly sessions of 60 minutes of combined aerobic-resistance exercise for 12-weeks; or a no exercise control group (n = 21). Both groups were evaluated at a baseline and after 12-weeks of exercise therapy for: 1) muscle strength and fatigue by isokinetic dynamometry; 2) plasma glycated hemoglobin A1C (HbA1C); and 3) HRQoL utilizing the SF-36 questionnaire. Results: the exercise therapy led to improvements in muscle fatigue in knee extensors (-55%) and increased muscle strength in knee flexors and extensors (+15 to +30%), while HbA1C decreased (-18%). In addition, the exercising patients showed sizeable improvements in HRQoL: physical function (+53%), vitality (+21%) and mental health (+40%). Conclusion: 12-weeks of combined aerobic-resistance exercise was highly effective to improve muscle strength and fatigue, glycemic control and several aspects of HRQoL in T2DM patients. These data encourage the use of aerobic and resistance exercise in the good clinical care of T2DM.

Variações anátomo-fisiológicas face à aclimatação sazonal - estudo em vacas leiteiras com diferente potencial leiteiro

O presente estudo teve como objetivo a caracterização de variações anátomo-fisiológicas que decorrem do processo de aclimatação sazonal em bovinos leiteiros com alto (Altas) e baixo (Baixas) potencial leiteiro, com vista a selecionar animais que conciliem bons desempenhos produtivos e índices de adaptabilidade que possibilitem a mudança de homeostase face às condições climáticas presentes no clima mediterrânico. O estudo foi realizado numa herdade comercial, situada no Alentejo, utilizando 13 vacas multíparas (6 Baixas e 7 Altas), durante três períodos: P1 (animais aclimatados ao verão; presença de stresse térmico); P2 (animais aclimatados ao verão; termoneutralidade); P3 (animais aclimatados ao inverno; termoneutralidade). Em stresse térmico (P1), verificaram-se maiores esforços termolíticos e maiores armazenamentos de calor no grupo das Altas. Observou-se também que a produção de leite das Altas foi afetada pelo stresse térmico, evidênciando uma redução 24-48h após os valores de temperatura retal mais elevados. Nesta situação, as Baixas apresentaram uma variação na produção oposta à das Altas. Em P1, os valores de proteína e de gordura no leite foram significativamente mais baixos que em P3, em ambos os grupos. A ureia no leite foi significativamente mais elevada nas Altas durante o P1, revelando potencial como biomarcador de stresse térmico. Do P1 para o P3 obser-vou-se uma redução gradual do hematócrito, da hemoglobina e da triiodotironina (T3). As Altas apresentaram uma maior redução de triiodotironina (T3) que as Baixas, como consequência de uma maior intensidade de aclimatação. Nos pelos não se registaram diferenças entre os períodos, o que contrasta com alguma bibliografia. Porém, a ausência da insolação direta poderá ter sido um fator determinante; ABSTRACT: The main objective of the present study was the characterization of anatomical and physiological variations that occur in the seasonal acclimatization process of dairy cows with high (Altas) and low (Baixas) milk yield potential. In this way it should be possible to do a selection of animals with good productive traits and also with adaptability indexes that allow a change in homeostasis to cope with the climatic conditions of the mediterranean climate. Meteorological, clinical, productive, physiological and anatomical data were collected. The study was conducted in an Alentejo's dairy farm, using 13 multiparous cows (6 with low milk yield and 7 with high milk yield), during three periods: P1 (animals acclimated to summer, in heat stress); P2 (animals acclimated to summer, thermoneutrality); P3 (animals acclimated to winter; thermoneutrality). In thermal stress (P1), the high milk yield group (Altas) shown greater thermolytic efforts and also higher heat storage. The milk yield in this group was also affected by heat stress, showing a decrease in production when the rectal temperature increased, with a delay of 24-42 hours. In this situation the Baixas group showed an opposite milk production variation. In P1, the protein and fat milk content was lower than in P3, in both groups. Milk urea levels were significantly higher during P1 in the Altas group, revealing potential as an heat stress biomarker. Hematocrit, hemoglobin and triiodothyronine (T3) values gradualy decreased from P1 to P3. T3 values were lower in Altas than in Baixas group, as a consequence of a more intense acclimatization. The hair analysis didn’t show the standard seasonal acclimatization process, indicating the absence of direct solar radiation as a determinant factor.