Puk Leick ny ph.d. studerende

Puk Leick er startet på sit ph.d.-projekt "The influence of physical activity on sleep quality, diurnal rhythm and their possible relationship with metabolic syndrome – a twin study" ...

    Puk Leick er uddannet cand. scient. på Københavns Universitet med dyreadfærd som speciale i 2007. Siden januar 2010 har hun været ansat som videnskabelig assistent på tvillingprojekt SAME, som er tilknyttet Institut for Regional Sundhedsforskning, Syddansk Universitet. Hendes hovedopgaver på dette projekt var som forskningslaborant i MEC (Mobil Examination Center), databehandler og udførsel af div. kontorarbejde. Den 1. oktober gik Puk i gang med sit ph.d.-studie: 

The influence of physical activity on sleep quality, diurnal rhythm and their possible relationship with metabolic syndrome – a twin study


A striking characteristic of many bodily functions is the rhythmical changes they manifest. These circadian rhythms, or biological clocks (with an approximately 24-hour cycle), ensures that we wake up but also that for instance the metabolism is prepared for increased activity. The circadian rhythms are synchronized with or entrained by the environment by external cues called zeitgebers, such as light, nutrients, external environmental temperature, and the feeding-fasting cycle. The mechanism underlying circadian rhythmicity is composed of a set of interlocking transcription/translation feedback loops of clock genes and proteins. It seem that variation of the clock genes may influence metabolism including insulin resisance. Also it has been suggested that disruption of the circadian rhythms (chronodisruption) may affect the risk of obesity, diabetes and other metabolic diseases. Furthermore, during the last ten years it is been increasingly evident that short sleep duration and poor quality of sleep can be of importance for endocrine and metabolic functions, probably because sleep is a major buffer for hormonal release, including for instance cortisol, glucose regulation and cardiovascular function. Further it has been shown in observational studies that working night shifts or suffering from sleeping disturbances are associated with obesity, and maybe also with insulin resistance and diabetes. Insufficient sleep may also reduce daytime physical activity, which promotes the already negative effect that sleep deprivation has on health. However, some population based studies have shown that regular exercise increases sleep duration and improves sleep quality, which consequently may influence metabolism and glucose homeostase.



The objective of this study i to study this complex interplay and in particular to examine whether physical activity modifies the possible risk that poor sleep quality have on the cortisol profil and on insulin resistance. Furthermore, it will be explored if and to what extent genetic factors influence the association between physical activity and sleep quality and sleep rhythm.