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Purpose: To study the effect of inhaling a beta-agonist (salbutamol) compared to placebo on skiing and cycling performance in well-trained elite athletes. Methods: Three different exercise protocols were used, all with a cross-over double blind placebo-controlled design. Participants inhaled 800 µg salbutamol or a placebo prior to the test, which was repeated on a following day with the participants inhaling the other substance. Fifteen junior elite skiers performed four free-style high intensity sprints (1100 m/work time 3.5–4.5 min). Twelve elite cyclists carried out a short cycling protocol, starting with two 5 min submaximal workloads followed by a maximal intermittent performance test to exhaustion. Another 12 elite cyclists performed the maximal intermittent performance test to exhaustion after a 150 min long submaximal cycling protocol. Results: Group mean time for the ski sprints increased, with no difference between treatment groups. In the short cycling protocol time to exhaustion was 9.1% (95% CI 52–161) lower after inhaling salbutamol compared to placebo and in the long cycling protocol time to exhaustion was 9.1% (95% CI – 121–267) lower after inhaling salbutamol compared to placebo. Blood lactate, heart rate and ventilation increased during submaximal exercise with salbutamol compared to placebo in the short cycling protocol (p <.05). Conclusion: This study could not confirm any positive performance effects from inhaling 800 µg salbutamol compared to placebo in skiing and high-intensity intermittent cycling performance. Instead, time to exhaustion in the maximal intermittent performance test was lower in both cycling protocols. Highlights There was no difference in performance time between salbutamol and placebo treatment in real-life applicable repeated ski sprints. Time to exhaustion in the maximal intermittent performance test was 9.1% lower after inhaling salbutamol compared to placebo, both when performed after 10 and 150 min of submaximal cycling. [ABSTRACT FROM AUTHOR]

This study was initiated due to the observation of increasing and rather high levels of stillbirths, especially in first-calving Swedish Holstein cows (10.3%, 2002). Seventy-six Swedish Holstein calves born to heifers at 41 different farms were post mortem examined in order to investigate possible reasons for stillbirth and at what time in relation to full-term gestation they had occurred. The definition of a stillborn calf was dead at birth or within 24 h after birth after at least 260 days of gestation. Eight calves were considered as having died already in uterus. Slightly less than half of the examined calves (46.1%) were classified as having died due to a difficult calving. Four calves (5.3%) had different kinds of malformations (heart defects, enlarged thymus, urine bladder defect). Approximately one third of the calves (31.6%) were clinically normal at full-term with no signs of malformation and born with no indication of difficulties at parturition or any other reason that could explain the stillbirth. The numbers of male and female calves were rather equally distributed within the groups. A wide variation in post mortem weights was seen in all groups, although a number of the calves in the group of clinically normal calves with unexplained reason of death were rather small and, compared with e.g. those calves categorised as having died due to a difficult calving, their average birth weight was 6 kg lower (39.9 ± 1.7 kg vs. 45.9 ± 1.5 kg, p ≤ 0.01). It was concluded that the cause of stillbirth with a non-infectious aetiology is likely to be multifactorial and difficult calving may explain only about half of the stillbirths. As much as one third of the calves seemed clinically normal with no obvious reason for death. This is a target group of calves that warrants a more thorough investigation in further studies.