Being a morning person is a behavioural indicator of a person’s underlying circadian rhythm. Using genome-wide data from 697,828 UK Biobank and 23andMe participants we increase the number of genetic loci associated with being a morning person from 24 to 351. Using data from 85,760 individuals with activity-monitor derived measures of sleep timing we find that the chronotype loci associate with sleep timing: the mean sleep timing of the 5% of individuals carrying the most morningness alleles is 25 min earlier than the 5% carrying the fewest. The loci are enriched for genes involved in circadian regulation, cAMP, glutamate and insulin signalling pathways, and those expressed in the retina, hindbrain, hypothalamus, and pituitary. Using Mendelian Randomisation, we show that being a morning person is causally associated with better mental health but does not affect BMI or risk of Type 2 diabetes. This study offers insights into circadian biology and its links to disease in humans.

This study examines the association between objectively measured access to green space, frequency of green space use, physical activity, and the probability of being overweight or obese in the city of Bristol, England. Data from the Bristol Quality of Life in your Neighbourhood survey for 6,821 adults were combined with a comprehensive GIS database of neighbourhood and green space characteristics.. A range of green space accessibility measures were computed. Associations between accessibility and the odds of respondents achieving a recommended 30 minutes or more of moderate activity five times a week, or being overweight or obese, were examined using logistic regression. Results showed that the reported frequency of green space use declined with increasing distance. The study also found that respondents living closest to the type of green space classified as a Formal park were more likely to achieve the physical activity recommendation and less likely to be overweight or obese. The association with physical activity, but not with overweight or obesity, remained after adjustment for respondent characteristics, area deprivation, and a range of characteristics of the neighbourhood environment. The findings suggest that the provision of good access to green spaces in urban areas may help promote population physical activity. IntroductionDespite the well recognised health benefits of regular physical activity and its role in reducing obesity, many people fail to achieve recommended activity levels; currently, only 37% of men and 24% of women in England and Wales meet the Chief Medical Officer's guidelines of 30 minutes of moderate exercise at least five days a week (Department of Health, 2005). Furthermore, over 25% of adult men and women are currently obese or overweight in the UK, for which physical inactivity is a well established risk factor (Pietiläinen, Kaprio, Borg, Plasqui, Yki-Järvinen, Kujala, et al., 2008). These figures are predicted to rise to over 50% in 2050 if current trends continue (Butland, Jebb, Kopelman, McPherson, Thomas, Mardell, et al., 2007).There is increasing evidence that the environment may play a role in influencing physical activity levels (Jones, Bentham, Foster, Hillsdon, & Panter, 2007). In particular, recent research has suggested that the provision of open spaces, such as parks and other green spaces, for recreation may provide an important place for people to be active (Macintyre, Macdonald, & Ellaway, 2008), especially in urban areas where gaining access to the open countryside can be difficult (Maas, Verheij, Spreeuwenberg, & Groenewegen, 2006). Mitchell & Popham (2008), recently highlighted lower levels of circulatory and all-cause mortality amongst English populations with the most green space in their surroundings, and a number of recent policy documents have promoted their potential benefits (e.g. CABE, 2004;National Heart Forum, 2007).The final published version of this article can be found at http://linkinghub.elsevier.com/retrieve/pii/S0277-9536(09)

The purpose of this multidisciplinary review paper is to critically review evidence from descriptive, efficacy and effectiveness studies concerned with physical activity and older people. Both levels of fitness (aerobic power, strength, flexibility and functional capability) and measures of physical activity involvement decline with age, and the extent to which this is due to a biological ageing processes or disuse (physical inactivity) is critically examined. The review will consider the evidence for a causal relationship between sedentary behaviour/physical activity programmes and cardiovascular, musculoskeletal and psycho-social health, independent living and health-related quality of life into old age. The review also considers the effectiveness of different physical activity interventions for older people and issues relating to cost-effectiveness. The implications for future policy in terms of research, health care services, and education and training are briefly discussed.

Background Little is known about the effectiveness of strategies to enable people to achieve and maintain recommended levels of physical activity. Objectives To assess the effectiveness of interventions designed to promote physical activity in adults aged 16 years and older, not living in an institution. Search methods We searched The Cochrane Library (issue 1 2005), MEDLINE, EMBASE, CINAHL, PsycLIT, BIDS ISI, SPORTDISCUS, SIGLE, SCISEARCH (from earliest dates available to December 2004). Reference lists of relevant articles were checked. No language restrictions were applied. Selection criteria Randomised controlled trials that compared different interventions to encourage sedentary adults not living in an institution to become physically active. Studies required a minimum of six months follow up from the start of the intervention to the collection of final data and either used an intention-to-treat analysis or, failing that, had no more than 20% loss to follow up. Data collection and analysis At least two reviewers independently assessed each study quality and extracted data. Study authors were contacted for additional information where necessary. Standardised mean differences and 95% confidence intervals were calculated for continuous measures of self-reported physical activity and cardio-respiratory fitness. For studies with dichotomous outcomes, odds ratios and 95% confidence intervals were calculated. Main results The effect of interventions on self-reported physical activity (19 studies; 7598 participants) was positive and moderate (pooled SMD random effects model 0.28 95% CI 0.15 to 0.41) as was the effect of interventions (11 studies; 2195 participants) on cardio-respiratory fitness (pooled SMD random effects model 0.52 95% CI 0.14 to 0.90). There was significant heterogeneity in the reported effects as well as heterogeneity in characteristics of the interventions. The heterogeneity in reported effects was reduced in higher quality studies, when physical activity was self-directed with some professional guidance and when there was on-going professional support. Authors’ conclusions Our review suggests that physical activity interventions have a moderate effect on self-reported physical activity, on achieving a predetermined level of physical activity and cardio-respiratory fitness. Due to the clinical and statistical heterogeneity of the studies, only limited conclusions can be drawn about the effectiveness of individual components of the interventions. Future studies should provide greater detail of the components of interventions.

Sleep is an essential human function but its regulation is poorly understood. Using accelerometer data from 85,670 UK Biobank participants, we perform a genome-wide association study of 8 derived sleep traits representing sleep quality, quantity and timing, and validate our findings in 5,819 individuals. We identify 47 genetic associations at P < 5 × 10 −8 , of which 20 reach a stricter threshold of P < 8 × 10 −10 . These include 26 novel associations with measures of sleep quality and 10 with nocturnal sleep duration. The majority of identified variants associate with a single sleep trait, except for variants previously associated with restless legs syndrome. For sleep duration we identify a missense variant (p.Tyr727Cys) in PDE11A as the likely causal variant. As a group, sleep quality loci are enriched for serotonin processing genes. Although accelerometer-derived measures of sleep are imperfect and may be affected by restless legs syndrome, these findings provide new biological insights into sleep compared to previous efforts based on self-report sleep measures.