None listed
Conditions
Brief summary
In this study, a number of specific between-groups hypotheses will be tested in the randomized controlled trial as detailed below: H1: Participants in the experimental group will experience improved sleep quality, relative to the study controls, between baseline and follow-up at 3-months; H2: Participants in the experimental group will lose a greater amount of weight, relative to the study controls, between baseline and follow-up at 3-months; Further, a number of within-subjects hypotheses will be tested: H3: The relationship between study group (i.e. hot/cold bath vs. study controls) and weight loss between baseline and 3-months follow-up will be mediated by the drop in mean core body temperature and improved sleep quality; and, H4: The relationship between study group and weight loss between baseline and 3-months will be mediated by a reduction in binge- and/or night-time eating, which is due to the longer time spent asleep and less time sitting up at night. That is, participants who do not engage in eating late at night are expected to lose more weight than those who do eat late at night. In the analyses pertaining to the hypotheses, we will control for all variables that are correlated with the outcome variables (i.e. sleep quality, and BMI), including symptoms of anxiety/ depression and a lack of exercise/physical activity, as well as certain conditions (e.g. hypothyroidism) or treatments (e.g. antidepressants), if appropriate.
Interventions
In this randomized controlled trial (RCT), we will evaluate the effects of instructing overweight/ obese individuals to take a hot or cold bath/shower (whichever is preferred) about 90-minutes prior to the time they wish to go to sleep, to determine whether this is effective in: (a) improving their sleep quality and increasing sleep times, and (b) as a consequence of going to bed earlier and sleeping a longer time, eat substantially less at night and therefore reduce their weight over time, rela
In this randomized controlled trial (RCT), we will evaluate the effects of instructing overweight/ obese individuals to take a hot or cold bath/shower (whichever is preferred) about 90-minutes prior to the time they wish to go to sleep, to determine whether this is effective in: (a) improving their sleep quality and increasing sleep times, and (b) as a consequence of going to bed earlier and sleeping a longer time, eat substantially less at night and therefore reduce their weight over time, relative to the control group participants. Based on the empirical studies where participants took a hot bath/shower as a modality of passive body heating (Allehe et al. 2013; Cynthia, 1996), the water temperature was 41-42 degrees Celsius. In our study, we will advise the participants who are taking a hot bath/shower to make it as hot as they feel comfortable with, which should be around this water temperature. However, it is important not to give too detailed instructions that are disparate in extent to the participants who instead seek to take a cold bath/show. The participants will also be asked to complete the study questionnaire prior to being randomized to a study group, then they will participate in their group’s activities for 3-months (i.e. reviewing and enacting the sleep hygiene information), and then completing the follow-up questionnaire. Finally, the intervention condition will involve the participants either taking a hot/cold bath or shower every night for 3-months, whichever is preferred), and completing the baseline and follow-up questionnaires. Several strategies will be used to ensure that the study participants do adhere to the instructions they received. First, we will instruct them to complete the diary as accurately as they can and remind them that we are not testing them, but rather the effectiveness of a potential new weight loss program. Third, we will telephone all participants (including the control group participants) after 1-week and 1-month to check on their engagement in their group activities, and to remind them to complete the questionnaire at the end of the study.
Sponsors
Australian National University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
Criteria for Inclusion Study inclusion criteria are as follows: (i) participants are required to be overweight or obese; (ii) over 18 years and less than 66 years of age, and (iii) able to bathe themselves or have a regular carer who can arrange this for them.
Exclusion criteria
Criteria for Exclusion: The study exclusion criteria are detailed as follows: including people who are: (i) under 18 years of age or older than 65-years; (ii) underweight or normal weight; or (iii) pregnant.
Outcome results
None listed