Human physical performance is influenced by genetic factors. A variation in the human angiotensin I-converting enzyme (ACE) gene has been identified, in which the insertion (I) variant may be associated with elite endurance performance, and the deletion (D) variant seems overrepresented amongst elite sprinters and short-distance swimmer status. We might thus anticipate I-allele frequency to be elevated amongst swimmers competing over very much greater distances, and have examined this hypothesis. Thirty-five truly elite very-long-distance swimmers were classified as better at 1- to 10-km distances (n=19, SLD group) or those best at 25-km races (n=16, LLD group). Genotype frequencies (II versus ID versus DD) differed between the two groups: 6% versus 47% versus 47% for SLD, and 18.8% versus 75% versus 6.2% for LLD (P=0.01). I-allele frequency was 0.29 for the shorter distance swimmers, and 0.59 for the 25 km group. These data are consistent with an association of ACE I allele with longer distance swimming, and the ACE D allele with swimming shorter distances.

Athletic endurance performance is probably partly under genetic control, but genetic association studies have yielded inconclusive results. The objective of the present study was to evaluate the association of polymorphisms in eight muscle- or metabolism-related genes with endurance performance in participants of the Olympus Marathon running race. We recruited 438 athletes who participated in the 2007 and 2008 annual running events of the Olympus Marathon: a 43.8-km race with an ascent from sea level to 2,690-m altitude and then a descent to 300 m. Phenotypes of interest were the competitive event time at the specific Olympus Marathon where the athlete was enrolled, the fastest reported timing ever achieved in an Olympus Marathon, and how many kilometers per week the athlete ran during the previous year. Eleven polymorphisms in alpha(3)-actinin (ACTN3), AMP deaminase-1 (AMPD1), bradykinin B(2) receptor (BDKRB2), beta(2)-adrenergic receptor (ADRB2), peroxisome proliferator-activated receptor (PPAR)-gamma coactivator-1 alpha (PPARGC1A), PPAR-alpha (PPARA), PPAR-delta (PPARD), and apoliprotein E (APOE) were evaluated. Hardy-Weinberg equilibrium testing on the overall cohort of male athletes showed a significant deviation for BDKRB2 rs1799722 (P = 0.018; P = 0.006 when limited to 316 habitual male runners) with an excess of the TT genotype. Across all athletes, no associations showed nominal statistical significance for any of the three phenotypes, and the same was true when analyses were limited to men (n = 417). When limited to 316 male athletes who identified running as their preferred sport, ADRB2 rs1042713 had nominally significant associations with faster times for the minor (A) allele for the fastest time ever (P = 0.01). The direction of effect was identical as previously postulated only for BDKRB2 rs1799722 and ADRB2 rs1042713, indicating consistency. BDKRB2 rs1799722 and ADRB2 rs1042713 have some support for being implicated in endurance performance among habitual runners and require further investigation.

The "insertion" (I) rather than "deletion" (D) variant of the human angiotensin-converting enzyme (ACE) gene is associated with both lower tissue ACE activity and elite performance at high altitude. We examined whether the onset of acute mountain sickness (AMS), and further performance on reaching the summit of Mt. Blanc are influenced by the ACE I/D polymorphism. Two hundred and eighty-four climbers (235 males, [37.0 (11.0 years], (86 DD, 142 ID, 56 II)) had assessment of their AMS status upon arrival to the Gouter hut (3,807 m) on day 1, and again on day 2 after an attempted ascent to the summit of Mt. Blanc (4,807 m). Success in reaching the summit was genotype dependent (87.7% of DD, 94.9% of ID and 100% of II individuals; P=0.048); I allele frequency for those reaching the summit was 0.47 compared to 0.21 for those who did not (P=0.01). The onset of AMS on day 1 appeared to be dependent on genotype (P=0.003), but with those heterozygous being less affected. ACE genotype was not associated either with AMS onset or severity on day 2. Thus, ACE I/D genotype is associated with successful high altitude ascent in this prospective study-an association not explicable by genotype-dependence of AMS onset or severity. Values are given as mean (SD) unless otherwise stated.

Objective To examine whether doctors' global assessments of treatment effects agree with patients' global assessments. Design Survey of trials included in systematic reviews of treatments for diverse conditions. Data sources Cochrane database of systematic reviews. Data extracted Data on patients' global assessments and on doctors' global assessment for the same treatment against the same comparator. Main outcome measures Relative odds ratio (ratio of odds ratios of global improvement with the experimental intervention versus control according to doctors compared with patients), and improvement rates according to doctors and patients. Results Doctors' global assessments were compared with patients' global assessments for 63 different treatment comparisons (240 trials) in 18 conditions. The summary relative odds ratio across the comparisons was not significant (0.98, 95% confidence interval 0.88 to 1.08; I 2 =0%, 95% confidence interval 0% to 30%). In 62 of the 63 comparisons the effects of treatment rated by patients and by doctors did not differ beyond chance, but for single comparisons the confidence intervals were large. Rates of improvement on average did not differ between doctors' assessments and patients' assessments (summary relative odds ratio 0.98, 0.88 to 1.06; I 2 =0%, 0% to 24%). Conclusion Doctors' global assessments of the effects of treatments are on average similar to those of patients. INTRODUCTIONFor several diseases and treatments the global assessment of change in disease status by patients and doctors are key outcomes for determining whether a treatment is effective. For some conditions other types of measurements besides an overall (global) impression are difficult, impractical, costly, or even non-existent. Global assessments have become popular choices as end points in selected disciplines, such as rheumatology, psychiatry, and dermatology, particularly when a single laboratory measurement or clinical measurement or documentation of an event cannot be used to adequately describe what happened to a study participant.An important question is whether patients and doctors agree in their assessment of treatment outcomes. Self assessment by patients may avoid bias by an external assessor, whereas doctors may be more objective than their patients. Doctors may consider additional aspects of conditions that are not assessable by patients and may have insight into whether patients tend to amplify or minimise symptoms.1 In theory, biases may be more likely when a study does not use blinding of doctors or patients, such as when blinding is impossible or compromised. Moreover, in different circumstances and for different diseases biases may operate differently between patients and doctorssome patients with mental or neurological diseases, for example, may be biased or inaccurate in the appraisal of their condition. Similarly, doctors may be inaccurate when they have few or no objective signs and tests on which to base their observations and have to use primarily patient reported information.S...

The aim of the study was to determine the factors affecting a climber's ability to ascend Mont Blanc using a number of variables collected at the Gouter Hut (3,817 m) before and after an attempted ascent on the Mont Blanc summit. Subjects (n=285) were tested at 3,817 m prior to their ascent of Mont Blanc. Maximum height ascended in the last 14 days was recorded. End tidal CO2, arterial oxygen saturation (SaO2), heart rate and respiratory rate were measured using a Capnograph (Nellcor Patrick NPB75). Acute mountain sickness (AMS) was assessed using the Lake Louise scoring system. Summit information is available for 216 subjects. None of the subjects who attained 4,000 m in the previous 14 days failed to reach the summit (P=0.04). Previous recent exposure to an altitude of 4,000 m resulted in faster ascent times to the summit than those who had not been above 3,000 m in the previous 14 days (4.02+/-0.6 vs. 4.46+/-0.8 h, P=0.009), higher SaO2 on arrival at the Gouter Hut on day 1 (88.6+/-5 vs. 86.3+/-6%, P=0.004) and lower AMS scores upon arrival at the Gouter Hut after the attempted ascent to the summit 2.5+/-1.8 versus 4.7+/-2.5 U (P=0.001), respectively. It is concluded that recent exposure to 4,000 m confers an advantage to those who wish to ascend a 4,800 m peak.