Our findings suggest an important role of estradiol in blunting the muscle damage response to intense eccentric exercise and preserving muscle function after EiMD.

This was a 48-week randomized single (observer) blind study in a teaching hospital rheumatology and physiotherapy department. The subjects were 74 patients who fulfilled the American College of Rheumatology criteria for fibromyalgia. Results and conclusions. A 12-week exercise class programme with home exercises demonstrated no benefit over a single physiotherapy session with home exercises in the treatment of pain in patients with fibromyalgia. Neither group (nor the groups combined) showed an improvement in pain compared with baseline. There was some significant benefit in psychological well-being in the exercise class group and perhaps a slowing of functional deterioration in this group.

In the present study, 200-m swim time in highly trained male swimmers was measured on two consecutive days (Trial 1 and Trial 2) and under three conditions [(1) acute loading, AcL; (2) chronic loading, ChL; (3) Placebo, PLA]. No sodium bicarbonate (NaHCO(3)) was administered between Trial 1 and Trial 2 under each condition. Blood lactate concentration ([La(-)]), base excess of extracellular fluid (BE(ecf)), plasma bicarbonate concentration ([HCO(3) (-)]) and pH were determined before and after capsule administration as well as at 0, 3, 5, 15 and 30 min after each 200-m swim trial. Swim time was not different among AcL, ChL or PLA for Trial 1 or 2 and we observed no change in 200-m swim time from Trial 1 to 2 under any condition (F = 0.48, P = 0.80). [HCO(3) (-)], pH and BE(ecf) measured after capsule administration was higher during AcL and ChL when compared with PLA (P < 0.05). We did not observe any difference in blood [La(-)] between the three conditions at any stage post-exercise (P > 0.05). The results indicate that acute and chronic loading of NaHCO(3) does not improve 200-m swim time in highly trained male swimmers.

The preservation of exercise tolerance during heavy-intensity cycling performed after intense eccentric exercise is improved in women compared to men. Furthermore, the preservation of exercise tolerance is exclusive to 17β-estradiol and cannot be replicated with an exogenous synthetic estrogen replacement delivered in an oral contraceptive.

We examined the effect of long-term oral contraceptive (OC) use on endurance performance in recreationally active women. Eight women using OC (OC group) and 8 women who were nonusers (CON group) performed a test to determine the peak oxygen uptake for cycling (V[Combining Dot Above]O2peak) and to estimate the anaerobic threshold (AT). Subjects also completed a continuous submaximal cycling test across 3 work stages (two 6-minute work stages below AT, and 1 above AT performed to exhaustion). Pulmonary gas exchange, heart rate (HR), blood pressure (BP), blood lactate concentration ([La]), and ratings of perceived exertion were measured throughout, and cycling economy was calculated. Physical characteristics were comparable between the groups (p > 0.05). Peak oxygen uptake (CON group: 2.59 ± 0.50 L·min; OC group: 2.13 ± 0.20 L·min) and oxygen uptake at the AT (CON group: 1.47 ± 0.27 L·min; OC group: 1.18 ± 0.15 L·min) were significantly different (p < 0.05) between the groups. Expired minute ventilation, HR, BP, [La], and cycling economy for all constant-load work stages were not significantly different (p > 0.05) between the groups. Furthermore, time to exhaustion for severe-intensity cycling was similar (p > 0.05) between the CON and OC groups. The results of the present study suggest that long-term OC use negatively affects peak V[Combining Dot Above]O2 and V[Combining Dot Above]O2 at the AT but does not alter endurance exercise performance.