Clinical trial NCT05880186: Influence of the Time of Day in the Effect of Caffeine on Maximal Fat Oxidation During Exercise in Women
Official title: Influence of the Time of Day in the Effect of Caffeine on Maximal Fat Oxidation During Exercise in Women. A Randomized, Crossover, Double-blind, and Placebo-controlled Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Dietary Supplement
Lead sponsor: Universidad Francisco de Vitoria
Sponsor class: OTHER
Collaborators: name: Universidad de Granada
name: Universidad Rey Juan Carlos
name: Camilo Jose Cela University
First posted: 2023-05-30
Enrollment: 14
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Dietary Supplement: caffeine acute supplementation
Primary purpose: TREATMENT

Brief summary: Caffeine is a natural stimulant with well-recognized metabolic benefits, however, there is a lack of studies investigating the time-of-day caffeine influence to enhance fat oxidation in women. The aim of this study was to evaluate the influence of the time of the day on the effect of caffeine on maximal rate of fat oxidation during aerobic exercise in women.

Detailed description: Caffeine is a natural stimulant with well-recognized sports performance benefits. Aside its performance-enhancing effect, caffeine has the potential of increasing fat utilization during aerobic exercise at submaximal intensities, lowering-down the contribution of carbohydrate as a fuel. This property of caffeine may provoke a glycogen-sparing effect in the skeletal muscle and liver for exercise situations where carbohydrate availability may be a challenge. Additionally, the capacity of caffeine to enhance fat utilization during exercise could be of interest for improving health outcomes as it may increase the rate of change in body composition in exercise programs. Maximal fat oxidation rate (MFO) during exercise is a remarkable physiological indicator associated with metabolic flexibility/body weight loss and endurance performance To date, it is unknown if caffeine increases MFO in the same proportion during morning and evening exercise trials in women. For this reason, the aim of the present study was to evaluate the influence of the time of the day on the effect of caffeine on MFO in women. We hypothesised that caffeine would increase MFO during morning and evening exercise and this effect would be of similar magnitude at both times of day.

Eligibility criteria: Inclusion Criteria:

* To be non-smokers.
* To have low caffeine intake (i.e., \< 50 mg of caffeine per day in the previous 2 months)
* To show no previous history of cardiopulmonary diseases or having suffered musculoskeletal injuries in the previous 6 months.
* To have a regular duration of their menstrual cycle for the previous 6 months.
* To confirm no existence of any type of menstrual disorders such as dysmenorrhea, amenorrhea, or strong symptoms associated with pre-menstrual syndrome.

Exclusion Criteria:

-

Primary outcomes:
measure: MFO
timeFrame: 2-months
Secondary outcomes:
measure: FATmax
timeFrame: 2-months
measure: RPE
timeFrame: 2-months
measure: FAT AND CHO oxidation
timeFrame: 2-months
Other outcomes:
Locations:
city: Pozuelo De Alarcón
country: Spain
facility: Universidad Francisco de Vitoria
state: Madrid
Study officials:
References: