(CSEMP002) ASSOCIATION OF PHYSICAL CAPACITY WITH LEVEL OF PHYSICAL ACTIVITY AND SLEEP IN WOMEN WITH OBESITY AND INFERTILITY

Background: It is recommended that women with obesity and infertility adopt healthy lifestyle habits before conception, like regular physical activity (PA) practice. Also, individuals with obesity frequently present reduced sleep quantity and quality, which could affect their PA practice. However, accurate and unbiased assessments of PA and sleep are difficult with questionnaires. Since physical capacity is related to PA practice in most individuals, it might be an indirect objective measure of a person's level of PA. Thus, our study aims to determine among women with obesity and infertility, the relationship between their physical capacity and reported levels of PA, as well as the association of these measures with their sleep quantity or quality.

METHODS AND RESULTS: This cross-sectional study is nested in a multicenter randomized controlled trial recruiting women of 18-40 years old with obesity and infertility in Canadian fertility clinics. At their initial research visit, they were assessed for weight, physical capacity (distance at 6-min walk test); total energy expenditure (EE, mets/week) and time spent for walking (min/week) or moderate to vigorous activities (MVPA, min/week) (International Physical Activity Questionnaire – Short Version (IPAQ)); as well as sleep quality and quantity (Pittsburgh sleep quality index questionnaire). Associations were tested using Spearman correlations. PA measures were Square-root-transformed to make their distribution normal for figures.

These preliminary analyses included 92 young women with a mean age of 31.45 and a mean BMI of 39.0, 77.2% were Caucasian and 74.8% had a level of education of a vocational diploma or higher. They were recruited in 4 centers with 51% being recruited at Sherbrooke, Quebec. Significant associations were found between physical capacity (n=85-86) and EE: rho=0.331, p=0.002; walking: rho=0.227, p=0.036; and MVPA: rho=0.317, p=0.003. Physical capacity was not associated with sleep quality (rho=0.021; p=0.846) or quantity (rho=0.046, p=0.671 (n=86). Finally, there was no association between parameters of PA levels and sleep quality or quantity (|rho| between 0.00 and 0.10, p>=0.35).

Conclusion: Our results show that the objective measure of physical capacity is moderately associated with PA practice, mainly total EE and time spent for moderate to vigorous activities, which suggests it is an indirect objective measure of PA practice. It also supports the convergent validity of the IPAQ questionnaire using an objective measure. However, there was no association between sleep and physical capacity or PA. Since questionnaires are subjective, it might be more appropriate to use objective methods to assess sleep and PA, such a wearable monitoring device.