Aerobic exercise capacity and pulmonary function in athletes with and without type 1 diabetes.

OBJECTIVE: To compare the aerobic exercise capacity and pulmonary function between athletes with and without type 1 diabetes. RESEARCH DESIGN AND METHODS: Fifty-one adult age-matched individuals were assessed in random order to the maximum volume of O(2) consumption (Vo(2 peak max)) (ml/kg/min), anaerobic threshold (ml/kg/min), peak pulmonary ventilation (Ve), heart rate (beats per min), time to exhaustion (min), forced vital capacity (FEV) (%), forced expiratory volume in the first second (FEV1) (%), total lung capacity (TLC) (%), and lung diffusion capacity for carbon monoxide (DL(CO)) (%). Individuals were 27 with type 1 diabetes: 15 athletes (ADM) and 12 nonathletes (NADM); and 24 healthy individuals: 12 ADM and 12 NADM. Duration of diabetes was 14.6 ± 6.2 and 15.2 ± 6.7 years in ADM and NADM, respectively. RESULTS: Vo(2 peak) (max) was higher in ADM than in NADM (P < 0.001). The anaerobic threshold was lower in subjects with type 1 diabetes than in control subjects (P < 0.001). FEV1 was lower in ADM than in other groups (NADM, athletes control, and nonathletes control, P < 0.001). CONCLUSIONS: Aerobic capacity in subjects with type 1 diabetes with programmed exercise is similar to the capacity of normal athletes despite lower anaerobic threshold and FEV1.

Maximal and submaximal physiological responses to adaptation to deep water running.

The aim of the study was to compare physiological responses between runners adapted and not adapted to deep water running at maximal intensity and the intensity equivalent to the ventilatory threshold. Seventeen runners, either adapted (n = 10) or not adapted (n = 7) to deep water running, participated in the study. Participants in both groups undertook a maximal treadmill running and deep water running graded exercise test in which cardiorespiratory variables were measured. Interactions between adaptation (adapted vs. non-adapted) and condition (treadmill running vs. deep water running) were analysed. The main effects of adaptation and condition were also analysed in isolation. Runners adapted to deep water running experienced less of a reduction in maximum oxygen consumption (VO2max) in deep water running compared with treadmill running than runners not adapted to deep water running. Maximal oxygen consumption, maximal heart rate, maximal ventilation, VO2max at the ventilatory threshold, heart rate at the ventilatory threshold, and ventilation at the ventilatory threshold were significantly higher during treadmill than deep water running. Therefore, we conclude that adaptation to deep water running reduces the difference in VO2max between the two modalities, possibly due to an increase in muscle recruitment. The results of this study support previous findings of a lower maximal and submaximal physiological response on deep water running for most of the measured parameters.

Avaliação do efeito da hipotermia por crioimersão corporal, nos neutrófilos e linfócitos sanguíneos de ratos submetidos ao exercício físico agudo / Evaluation of the effect of hypothermia by cold water immersion on blood neutrophils and lymphocytes of rats submitted to acute exercise

O estresse sistêmico induzido pelo exercício libera substâncias bioativas determinantes da mobilização neutrofílica. A crioterapia diminui a reação inflamatória e atenua a elevação da perfusão sanguínea induzida pelo exercício. O objetivo deste trabalho foi analisar a influência da hipotermia decorrente da crioimersão corporal (CIC) imediata ao esforço físico agudo nas concentrações neutrofílicas e linfocíticas no sangue. Os ratos do grupo controle (AI) foram mantidos em repouso enquanto os do grupo AII foram submetidos ao protocolo de CIC a 10ºC por 10 minutos. Enquanto os animais dos grupos BI, BII, BIII e BIV realizaram o esforço físico agudo (EFA) em água a 31ºC durante 100 minutos com sobrecarga corpórea de 5% do peso corporal, os dos grupos CI, CII, CIII e CIV foram submetidos ao EFA seguido imediatamente de CIC. Nos grupos B e C, os animais foram sacrificados nos períodos de 06 (I), 12 (II), 24 (III) e 48 (IV) horas posteriores ao EFA. Através da microscopia óptica realizou-se a contagem dos neutrófilos e linfócitos. Utilizou-se do Teste T Student para análise estatística considerando-se nível de significância p < 0,05. Observou-se uma significativa neutrofilia nos grupos AII, BI, BII, BIII, BIV, CI, CII e CIII em relação a AI, diferentemente do grupo CIV, que apresentou quantidade de neutrófilos igual ao grupo controle. Os valores de linfócitos nos grupos BII, BIII, BIV, CI e CII foram significativamente menores do que AI, e nos grupos AII, BI, CIII e CIV foram iguais a AI. A neutrofilia e a linfopenia posteriores ao intenso exercício agudo são mantidas por 48 horas ou mais, porém, mediante a aplicação da crioimersão corporal imediata ao exercício, são normalizadas em 24 horas.

Systemic stress induced by exercise increases bioactive substances in plasma which leads to neutrophilic mobilization. Cryotherapy causes a decrease in the inflammatory reaction and attenuates high blood perfusion after exercise. The objective of this work was to analyze the influence of cold water immersion (CWI) after acute exercise on neutrophil and lymphocyte mobilization. A control group of rats (AI) was kept at rest and a second group (AII) was submitted to CWI at 10º C for 10 minutes. The animals of Groups BI, BII, BIII and BIV were submitted to acute exercise which consisted in swimming in water at 31º C for 100 minutes with a load equivalent to 5% of the body weight. Groups CI, CII, CIII and CIV were submitted to CWI immediately after acute exercise. The animals were sacrificed at 6 (I), 12 (II), 24 (III) and 48 (IV) hours after the exercise and neutrophil and lymphocyte cells were counted for all groups by optic microscopy. The Student t-test was used for statistical analysis with a significance level of p< 0.05. A significant increase in the number of neutrophils was observed in Groups AII, BI, BII, BIII, BIV, CI, CII and CIII compared to AI. The neutrophil count of the CIV Group was similar to the Control Group. There was a significant drop in the number of lymphocytes in Groups BII, BIII, BIV, CI and CII when compared to Group AI. The lymphocyte count of Groups AII, BI, CIII and CIV were similar to the Control Group. The changes in neutrophil and lymphocyte counts caused by acute exercise were reverted to normal at 24 hours by cold water immersion.

Growth hormone replacement improves thyroxine biological effects: implications for management of central hypothyroidism.

CONTEXT: The biological significance of GH-induced changes in serum TH concentrations is unknown. It has been suggested that serum free T(4) (FT(4)) should be targeted at the high-normal range during GH replacement. OBJECTIVE: Our objective was to evaluate the effects of GH replacement on T(4) biological effects. HYPOTHESIS: If GH modulates thyroxine biological effects, serum FT(4) should be targeted accordingly. DESIGN AND SETTING: We conducted observational (study 1) and interventional (studies 2 and 3)/outpatient studies. PATIENTS: Thirty-two GH-deficient patients (13 off GH; 22 on l-T(4)) participated in the study. INTERVENTIONS: In study 2, levothyroxine was administered to increase FT(4) (>1.0 ng/dl). In study 3, GH was administered or withdrawn. MAIN OUTCOME MEASURES: We measured FT(4), total T(3) (TT(3)), myocardial isovolumic contraction time (ICT), and resting energy expenditure (REE). RESULTS: In study 1, off-GH and on-GH groups had similar FT(4), but off GH showed lower TT(3) (P < 0.01) and REE (P = 0.02), higher ICT (P < 0.05) than on-GH and controls. On GH, ICT and REE correlated only with TT(3) (r = -0.48; r = 0.58; P < 0.05). Off GH, ICT correlated only with FT(4) (P < 0.01). In study 2, off GH, levothyroxine intervention increased FT(4) (P = 0.005) and TT(3) (P = 0.012), decreased ICT (P = 0.006), and increased REE (P = 0.013); ICT and FT(4) changes correlated (r = -0.72; P = 0.06). On GH, levothyroxine increased FT(4) (P = 0.0002), TT(3) (P = 0.014), and REE (P = 0.10) and decreased ICT (P = 0.049); REE and TT(3) changes correlated (r = 0.60; P = 0.05). In study 3, GH decreased FT(4), increased TT(3), decreased ICT, and increased REE (P < 0.05). REE correlated (P < 0.05) with IGF-I (r = 0.57) and TT(3) (r = 0.64). ICT correlated only with TT(3) (r = -0.46). CONCLUSIONS: GH replacement improves the biological effects of T(4). Serum FT(4) should be targeted at the high-normal range in GH-deficient patients only off GH replacement.

Consumo de oxigênio e condicionamento físico em pacientes com lúpus eritematoso sistêmico / Oxygen consumption and aerobic conditioning in patients with systemic lupus erythematosus

Os autores fazem uma introdução aos conceitos sobre testes cardiorrespiratórios, mecanismos de adaptação de transporte de oxigênio durante o exercício, consumo de oxigênio e consumo máximo de oxigênio. Também fazem uma revisão da literatura sobre trabalhos avaliando a tolerância ao exercício e condicionamento cardiovascular em pacientes com LES.

Artrite reumatóide: treinamento cardiovascular / Rheumatoid arthritis: Cardiovascular training

Artrite reumatóide (AR), doença inflamatória sistêmica, tem sido estudada quanto aos aspectos de capacidade funcional, gasto energético e condicionamento cardiovascular. Os pacientes com AR apresentam redução da força e resistência muscular, fadiga, depressão e auto-estima diminuída, com a expectativa de vida reduzida em média de 10 a 15 anos. Considerando o grau de comprometimento desses pacientes, nesta revisão discute-se como um programa de treinamento cardiovascular pode contribuir para a melhora no consumo de oxigênio e índices cardíacos e, assim, de sua qualidade de vida