Modelling of Energy Expenditure From Heart Rate, Accelerometry and Other Physiological Parameters
Condition: Computer Simulation; Energy Expenditure; Energy Metabolism
Study type: Interventional

Summary: 
      At this time, 24h energy expenditure is rarely assessed under free-living conditions for
      specific individuals because of the lack of cheap and accurate software/materials to record
      the energy expenditure. Some affordable and convenient tools (Polar heart rate monitor,
      Actiheart, SenseWear Armband) are available on the market but the predictive equations
      comprised into the software provided with these tools generally miscalculate the energy
      expenditure (by about +/-10%). Because of this deficiency, the investigators have a poor
      knowledge of the modification of the energy expended during daily life activities and over
      24h in subjects belonging to groups of various ages and physiological states. The
      investigators hypothesise that it could be possible to improve the energy expenditure
      prediction.

      The project aims at providing a mathematical model (equations) that predicts energy
      expenditure with an error near to 5%. Two groups of 60 sedentary to athletic normal weight
      volunteers aged between 18-60 years participate to this study. The first group stay for 26h
      in calorimetric chambers. During this stay energy expenditure ,heart rate, accelerometry, and
      other parameters are recorded during various activities. These data will serve to construct
      the model. The same type of recordings are performed on second group of volunteers in free
      living conditions. Their energy expenditure is measured overall by doubly labeled water. The
      data of the second group will serve to validate the model. The error percentage of the model
      is defined by the ratio of the value of the difference between prediction and reference
      measure to the reference measure. Concordance between predictions and measures will be
      evaluated by Bland - Altman plots.
    

Detailed description: 
      All the volunteers have a visit of inclusion in the Centre de Recherche en Nutrition Humaine.
      During this visit, the volunteers are informed of the methods of the protocol, the taking of
      samples, the disadvantages and constraints, on the basis of information letter. They have a
      medical interrogation and a complete clinical examination by an investigatory doctor or
      Co-investigator. The biological assessment is requiring 10 ml of blood and including: the
      analysis of the TSH, a blood count, a sedimentation test. Moreover, for the women in age to
      procreate, the analysis of the beta - HCG is made. To take another blood sample (10 ml) is
      necessary for the realization of serology HIV/HCV in the volunteers of the group of doubly
      labeled water, who provide samples of urine and saliva. The results are communicated to the
      volunteers confidentially.

      Following the visit of inclusion and the signature of the consent form, a food consumption
      survey is performed to evaluate the energy intakes of the volunteers. Moreover, the body
      composition and the level of physical-activity of the volunteers are evaluated by biphotonic
      absorptiometry (DEXA) and using questionnaire MAQ (Modifiable Activity Questionnaire,
      translated and adapted by Vuillemin and Al, 1999), respectively.

      The volunteers of the first group (60) performed a maximal aerobic power test on ergocycle to
      evaluate their maximum aerobic physical capacity (VO2max), in a hospital laboratory. A
      measurement of the body composition by biphotonic absorptiometry is also carried out to
      determine their lean and fat mass. Then, the volunteers stay 26 hours in calorimetric rooms
      (one evening, one night and a day). The data of indirect calorimetry (O2 consumption and
      production of CO2), heart rate , actimetry and other parameters are taken into account as
      from midnight. After one night of sleep, the individuals have to carry out series of state or
      exercises simulating the daily physical-activities (sleeping, writing 15 min,
      standing-sitting 5 min, standing 15 min, strolling 15 min, rest 20 min, eating 20 min,
      household 20 min, stepper 20 min, walking on treadmill at increasing speed 3 km/h, 4 km/h, 5
      km/h and 6 km/h during 20 minutes). The volunteers have also to answer questionnaires on
      their perception of hunger, their emotional state and their visual appreciation of 6 food
      products at 5 times of the day (before and after the breakfast, before and after the lunch
      and about 16:30 pm). The rest of the time, their activities are free (watching TV, reading,
      listening radio …). Measurements finish towards 18:00 and volunteers go home. The meals are
      balanced in proteins/glucides/lipids and cover energy needs. The menus are established by the
      dieticians. The meals in calorimetric room are prepared in double weighing to make it
      possible to calculate the actual quantities.

      The second group of volunteers (60) follow the protocol of doubly labeled water to evaluate
      their energy expenditure during 10 days in free living conditions. For this period, their
      heart rate, parameters of actimetry and other parameters are recorded . The participants of
      this second group also answer the questionnaires of perception of hunger, emotional state and
      visual appreciation of 6 food products, over one day at home. The physical data recorded on
      this second group will be introduced into the predictive equations. The estimated energy
      expenditure will be compared with the energy expenditure measured by the technique of doubly
      labeled water. The answers to the questionnaires filled out by the volunteers of the two
      groups will be also compared.
    

Intervention name(s): calorimetric chamber; Free living conditions
Intervention type(s): Device; Device
Intervention description(s): Participants stayed 26h in a calorimetric chamber. They performed a series of physical activities such as walking on a treadmill at different speeds, writing, standing, standing-sitting, stepper , rest , sleeping and eating. They also performed a power test on an ergocycle at different speeds.; Volunteers followed the protocol of doubly labeled water to evaluate their energy expenditure during 10 days in free living conditions. For this period, their heart rate, parameters of actimetry and other parameters were recorded.
Other intervention name(s): indirect calorimetry; Doubly labeled water
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: energy expenditure; heart rate; accelerometry; body temperature; heat flow galvanic response of skin