Clinical trial NCT05810272: Impact of Postprandial 'Exercise Snacks' on Protein and Glucose Metabolism Following a Period of Step Reduction in Older Adults
Official title: The Impact of Postprandial 'Exercise Snacks' on Protein and Glucose Metabolism Following a Period of Step Reduction in Older Adults
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Inactivity, Physical
Aging
Healthy Aging
Sarcopenia
Muscular Atrophy
Neuromuscular Manifestations
Neurologic Manifestations
Nervous System Diseases
Atrophy
Pathological Conditions, Anatomical
Keywords: Skeletal Muscle
Step-Reduction
Aging
Anabolic Resistance
Physical Activity
Stable Isotopes
Lead sponsor: University of Toronto
Sponsor class: OTHER
First posted: 2023-04-12
Enrollment: 20
Sex: ALL
Minimum age (years): 60
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: OTHER

Brief summary: The purpose of this study is to assess the impact of 3-days reduced physical activity (\<1500 steps/day) with/without 'exercise snacks' (15 chair stands with calf raises every 30 min) on skeletal muscle metabolic health.

Detailed description: Many adults gradually lose muscle size, strength, and function after the age of 50. These losses are believed to occur faster with periods of reduced activity (e.g., lower step counts or physical movement when sick or injured) and can be difficult to regain by merely returning to a previously normal activity status. Such periods of reduced activity can also impair the body's ability to use the nutrients in the food consumed (e.g., proteins and carbohydrates), which increases the risk of frailty, type 2 diabetes, and ultimately a reduced quality of life. It is important to identify strategies to prevent these losses in muscle size, strength, and function especially during periods of reduced activity.

Recently, our laboratory has found that performing repeated bodyweight chair squats (repeated sit-to-stands with a calf raise) during a single day of reduced activity improves the muscle's ability to use carbohydrates and proteins, which may be a viable strategy to offset the negative effects of step reduction on muscle health.

In this study, the investigators will assess whether completing bodyweight chair squats at regular intervals (i.e., 'exercise snacks') reduces the negative effects of step reduction on carbohydrate and protein metabolism following a meal. The investigators will determine the impact of 'exercise snacks' (15 chair stands with calf raises every 30 min) compared to seated rest on protein and carbohydrate metabolism following three days of step reduction. The investigators will also assess how these responses compare to those seen following three days of normal (i.e., habitual) activity.

Eligibility criteria: Inclusion Criteria:

* Healthy older (age: 60-80 y) adults
* BMI between normal to overweight (18.5-29.9 kg/m2)

Exclusion Criteria:

* Regular use of nonsteroidal anti-inflammatory drugs (with the exception of daily low-dose aspirin)
* Alcohol consumption during the study period
* Use of anticoagulants
* Use of a walker, cane, or assistive walking device
* Current or recently remised cancer
* Infectious or gastrointestinal disease
* Inability to comply with study protocol (e.g., \>1,500 steps/day during Step-Reduction Phase)
* Regular tobacco use
* Self-reported illicit drug use (e.g. growth hormone, testosterone, etc.)
* Diagnosed chronic illness (e.g. type 2 diabetes, heart disease, thyroid disease)
* Hormonal Replacement Therapy

Primary outcomes:
measure: Myofibrillar protein synthesis rates
timeFrame: 5 Hours
Secondary outcomes:
measure: Whole-body protein turnover
timeFrame: 5 Hours
measure: Amino acid oxidation and net protein balance
timeFrame: 5 Hours
measure: Postprandial insulin area under the curve (AUC) to mixed macronutrient breakfast
timeFrame: 5 Hours postprandial
measure: Postprandial glucose area under the curve (AUC) to mixed macronutrient breakfast
timeFrame: 5 hours postprandial
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Goldring Center for High Performance Sport
state: Ontario
Study officials:
affiliation: University of Toronto
name: Daniel R Moore, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Toronto
name: Hugo JW Fung, PhD
role: STUDY_DIRECTOR
References: