Seasonal Patterns of Stress, Diet and Physical Activity - Life in All Seasons (LENAS)
Condition: Obesity; Stress; Feeding Behavior; Physical Activity
MeSH terms: Obesity
Study type: Observational

Summary: 
      The purpose of this study is to develop a better understanding of factors affecting
      American's energy balance related behaviors - in this case, food intake and activity. In the
      present study we will describe the relative contributions of individual psychology and
      physiology (including metabolism, mood, and sleep habits) and external (season, stressors)
      contributions to changes in adiposity over a year in free-living individuals.

      This study will illuminate season's role in changes in energy balance related behaviors and
      body weight and composition. Ultimately, this information will be used to identify factors
      affecting food consumption and individual activity during seasonal periods to help to segment
      interventions for obesity prevention in mid-life women.
    

Detailed description: 
      This is a longitudinal, observational study of mid-life women spanning one year.There will be
      frequent monitoring of food consumption, individual activity and individual- level factors
      thought to influence food consumption and activity such as dietary restraint, subjective
      stress, sleep quality and duration, and physiological stress as measured by allostatic load.

      Specific aims:

        1. To identify seasonal changes in %BF of mid-life women.

           Participant's percentage of body fat will fluctuate, and will be highest at the end of
           the winter season and lowest at the end of the summer season.

        2. To describe predictors of seasonal changes in %BF.

      There will be no intervention other than frequent monitoring of food consumption, individual
      activity and individual- level factors thought to influence food consumption and activity
      such as dietary restraint, subjective stress, sleep quality and duration, and physiological
      stress as measured by allostatic load. The volunteers will be asked to complete a 7-day
      activity and energy expenditure monitoring period (along with body composition assessment,
      questionnaires regarding individual factors thought to affect food consumption and activity,
      blood draw and urine collection to measure allostatic load) in each of the four seasons over
      a 12-month period; between monitoring periods they will come to the GFHNRC for measurement of
      weight, skin carotenoids for assessment of fruit and vegetable intake, and to provide a
      morning urine sample monthly (8 times), and receive emails reminding them to log on to a
      secure server and complete a 24-hr recall 3 times a month (36 times during the year).

      The ASA-24 will be administered to assess nutritional intake; Actigraph GT3X+, Actitrainer,
      and QStarz GPS logger will be used to assess physical activity. Physiological stress will be
      assessed using the allostatic load index.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Middle-aged females
      
Biospecimen description: 
      Serum, Plasma, Buffy Coat, Urine, Saliva
    
Keywords: Body Weight/physiology*; Diet*/statistics & numerical data; Diet*/trends; Exercise/physiology*; Female; Humans; Longitudinal Studies; Middle Aged; Obesity/epidemiology*; Seasons*; Time Factors