Healthy Active Females
Conditions
Brief summary
The objective of this study is to examine the effects of time-restricted feeding (TRF; consuming all calories within an 8-hour period of time each day) and resistance training, with or without the addition of the dietary supplement HMB, on body composition, muscular performance and physiological outcomes in active females.
Interventions
DIETARY_SUPPLEMENTBeta-hydroxy beta-methylbutyrate
3 grams per day of the calcium salt form of beta-hydroxy beta-methylbutyrate (HMB).
OTHERResistance Training
Performing supervised resistance training three times per week.
DIETARY_SUPPLEMENTProtein Supplementation
Consuming a protein supplement daily.
BEHAVIORALTime-Restricted Feeding
Consuming all calories within a specified 8-hour period of time each day.
Sponsors
Metabolic Technologies Inc.
Dymatize Enterprises, LLC
Texas Tech University
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
OTHER
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Masking description
Investigators and participants will be blinded to dietary supplement (i.e. HMB or placebo). However, neither the investigators nor participants will be blinded to dietary intervention (TRF or ND) due to the nature of these dietary programs. When possible, outcome assessors will be blinded to group assignment.
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Female between 18 and 30 years of age * Current university affiliation * Weighing at least 110 pounds * Generally healthy * Resistance-trained * Schedule availability to complete supervised resistance training * Body fat percentage between 15 and 29%
Exclusion criteria
* Pregnant or trying to become pregnant * Currently breastfeeding * Any disease, condition or orthopedic limitation that would prevent safe participation in resistance training or time-restricted feeding * Current smoker * Presence of pacemaker or other electrical implant * Allergic to dairy proteins
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Fat mass | 8 weeks | Assessed using multi-compartment model |
| Fat-free mass | 8 weeks | Assessed using multi-compartment model |
| Body fat percentage | 8 weeks | Assessed using multi-compartment model |
| Upper body muscle hypertrophy | 8 weeks | Muscle thickness of elbow flexor muscles |
| Lower body muscle hypertrophy | 8 weeks | Muscle thickness of knee extensor muscles |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Lower body muscular endurance | 8 weeks | Assessed by repetitions to failure on leg press |
| Upper body muscular strength | 8 weeks | Assessed by 1RM on bench press |
| Upper body muscular endurance | 8 weeks | Assessed by repetitions to failure on bench press |
| Cortisol awakening response | 8 weeks | Assessed via analysis of saliva samples |
| Lipid panel | 8 weeks | Measured from fasted blood sample |
| Blood glucose | 8 weeks | Measured from fasted blood sample |
| Eating behavior | 8 weeks | Assessed by three-factor eating questionnaire R18 |
| Blood C-reactive protein | 8 weeks | Measured from fasted blood sample |
| Blood pressure | 8 weeks | Measured using automated device |
| Arterial compliance | 8 weeks | Assessed by applanation tonometry |
| Resting metabolic rate | 8 weeks | Assessed by indirect calorimetry |
| Respiratory quotient | 8 weeks | Assessed by indirect calorimetry |
| Mood | 8 weeks | Assessed by questionnaire |
| Blood insulin | 8 weeks | Measured from fasted blood sample |
| Sleep quality | 8 weeks | Assessed by Pittsburgh Sleep Quality Index |
| Physical activity level | 8 weeks | Assessed by accelerometry. |
| Lower body muscular strength | 8 weeks | Assessed by 1RM on leg press |
| Lower body muscular power characteristics | 8 weeks | Assessed during vertical jump and isometric squats |
Countries
United States
Outcome results
None listed