Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
There is a distinct lack of experimental evidence on whether breakfast consumption and omission affect energy balance-related variables. This research is of particular relevance to adolescent girls due to concerns of low rates of breakfast consumption and physical activity in this population. This study aims to compare the effect of seven consecutive days of breakfast omission with standardised breakfast consumption on free-living physical activity energy expenditure, energy intake and perceived appetite and energy levels in adolescent girls.
Observational reports showing infrequent breakfast consumption to be associated with increased adiposity and cardiometabolic disease risk in children and adolescents have fuelled concerns over the low prevalence of habitual breakfast consumption among adolescents. Yet, only experimental study designs can determine the causal effects of breakfast consumption on health-related variables and such research has typically targeted adults. Adolescent girls may respond differently to manipulations in breakfast consumption than adults because they have distinct hormonal, metabolic and behavioural profiles. Further, a link between breakfast and physical activity in adolescent girls has particular public health relevance because the adolescent decline in both breakfast consumption frequency and physical activity is more pronounced in girls than in boys. Thus, the primary aim of the current study is to use a randomised, cross-over design to compare the effect of seven consecutive days of breakfast omission with standardised breakfast consumption on free-living PAEE in adolescent girls. The secondary aims are to examine the effects on energy intake, perceived appetite and energy levels.
Using a randomized crossover design, girls aged 11-14 years will complete two, 7-day conditions. A standardized breakfast will consumed every day before 09:00 in the daily breakfast consumption condition. No energy-providing nutrients will consumed (i.e., only water) before 10:30 in the breakfast omission condition. Combined heart rate-accelerometry will be used to estimate physical activity energy expenditure and digital photography complemented with written food diaries will be used to assess energy intake during each condition; these data will be separated into three time segments: wake to 10:30, 10:30 to 15:30 and 15:30 to bed. Visual analogue scales will be used to assess perceptions of hunger, fullness, tiredness and energy levels on waking and at 09:00 and 10:30. Statistical analyses will be completed using condition by time of day linear mixed models.
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Breakfast consumption | Experimental | Participants will be asked to consume a standardised breakfast at home before 09:00 for seven consecutive days. The energy content of the breakfast will be 25% of individual measured resting metabolic rate. Prior to the experimental conditions, the participants will select one wholegrain, high-fibre ready-to-eat cereals (with the option of adding raisins) and fruit juice from a limited selection. Thus, breakfast composition will be controlled within participants, but not between participants to account for individual preferences. To ensure that the correct amount of each breakfast item is consumed, food items will be provided to the participants in pre-packaged containers and the participants will be provided with a marked beaker to measure their milk and juice each morning. The only exception is that parents will be asked to provide the 1.8% milk. |
|
| Breakfast omission | Experimental | Participants were asked to abstain from all energy-providing nutrients before 10:30 for seven consecutive days. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Breakfast consumption | Other | Standardised breakfast consumption across seven days |
| |
| Measure | Description | Time Frame |
|---|---|---|
| Physical activity energy expenditure (kJ/day) | Free-living physical activity energy expenditure from sedentary, light, moderate and vigorous activities (kJ/day) assessed using combined heart rate-accelerometry across seven consecutive days. | Seven days |
| Time spent in physical activity (minutes/day) | Time spent sedentary and in light, moderate and vigorous physical activity (minutes/day) assessed using combined heart rate-accelerometry across seven consecutive days. | Seven days |
| Measure | Description | Time Frame |
|---|---|---|
| Energy intake (kJ/day) | Energy intake (kJ/day) assessed using combined digital photography and food diaries across four days. | Four days |
| Carbohydrate intake (g/day) | Carbohydrate intake (g/day) assessed using combined digital photography and food diaries across four days. |
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Affiliation | Role |
|---|---|---|
| Julia K Fruer, PhD | University of Bedfordshire | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| University of Bedfordshire | Bedford | Bedfordshire | MK41 9EA | United Kingdom |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| ID | Term |
|---|---|
| D063766 | Pediatric Obesity |
| D007333 | Insulin Resistance |
| D000294 | Adolescent Behavior |
| D009043 | Motor Activity |
| D057185 | Sedentary Behavior |
| ID | Term |
|---|---|
| D009765 | Obesity |
| D050177 | Overweight |
| D044343 | Overnutrition |
| D009748 | Nutrition Disorders |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Breakfast omission |
| Other |
No breakfast consumed across seven days |
|
| Four days |
| Fat intake (g/day) | Fat intake (g/day) assessed using combined digital photography and food diaries across four days. | Four days |
| Protein intake (g/day) | Protein intake (g/day) assessed using combined digital photography and food diaries across four days. | Four days |
| Fibre intake (g/day) | Fibre intake (g/day) assessed using combined digital photography and food diaries across four days. | Four days |
| Perceived hunger (mm) | Perceived hunger (mm) assessed using 0-100 mm visual analogue scales on waking, at 09:00 and at 10:30 on four days. Higher values equate to higher hunger. | Four days |
| Perceived fullness (mm) | Perceived fullness (mm) assessed using 0-100 mm visual analogue scales on waking, at 09:00 and at 10:30 on four days. Higher values equate to higher fullness. | Four days |
| Perceived tiredness levels (mm) | Perceived tiredness levels (mm) assessed using 0-100 mm visual analogue scales on waking, at 09:00 and at 10:30 on four days. Higher values equate to higher tiredness. | Four days |
| Perceived energy levels (mm) | Perceived energy levels (mm) assessed using 0-100 mm visual analogue scales on waking, at 09:00 and at 10:30 on four days. Higher values equate to higher energy levels. | Four days |
| D009750 |
| Nutritional and Metabolic Diseases |
| D001835 | Body Weight |
| D012816 | Signs and Symptoms |
| D013568 | Pathological Conditions, Signs and Symptoms |
| D006946 | Hyperinsulinism |
| D044882 | Glucose Metabolism Disorders |
| D008659 | Metabolic Diseases |
| D001519 | Behavior |