Two-Week Stair-Climbing Exercise Snacks and Metabolic Health in Adults With Overweight or Obesity: A Pilot Study

Effects of a Two-Week Stair-Climbing "Exercise Snacks" Intervention on Body Composition, Cardiovascular Fitness, and Metabolic Responses in Overweight and Obese Adults: A Pilot Study

This pilot study will evaluate whether brief bouts of stair climbing performed throughout the day for two weeks can improve metabolic health, cardiovascular fitness, and other health-related outcomes in adults with overweight or obesity who do not regularly exercise. Participants will complete approximately 6-8 brief stair-climbing "exercise snacks" per day for 14 days, with each bout consisting of approximately 60 total stair steps performed at a challenging but safe self-selected pace.

Participants will complete baseline and post-intervention assessments at Saint Louis University. These assessments will include continuous glucose monitoring and standardized meal testing to evaluate glucose responses, as well as measures of aerobic fitness, anaerobic power, body composition, waist circumference, and muscular strength. The study will also evaluate adherence, perceived exercise intensity, and the feasibility of incorporating brief stair-climbing bouts into daily life.

Study Overview

• Status: Recruiting
• Conditions: Overweight , Obesity
• Intervention / Treatment: Behavioral: Stair-Climbing Exercise Snacks

Detailed Description

This is a pilot intervention study designed to examine the short-term effects and feasibility of frequent stair-climbing "exercise snacks" in adults with overweight or obesity. Exercise snacks are brief bouts of physical activity performed intermittently throughout the day and may provide a time-efficient approach to increasing physical activity.

The study will enroll approximately 12 adults aged 18-35 years with a body mass index of 25.0-34.9 kg/m² who are otherwise healthy and do not regularly participate in structured exercise. Participants must have regular access to a safe staircase.

Participants will complete three in-person study visits at Saint Louis University over approximately 15-16 days. Baseline assessments will include anthropometric and body composition measurements, resting cardiovascular measures, handgrip strength, aerobic fitness testing, and anaerobic power testing. Participants will also complete a standardized meal challenge while wearing a continuous glucose monitor to assess postprandial glucose responses.

Following baseline testing, participants will complete a two-week stair-climbing intervention. They will perform approximately 6-8 stair-climbing bouts per day for approximately 14 days. Each bout will consist of approximately 60 total stair steps completed at a self-selected challenging but safe pace. Participants may use one or more flights of stairs repeatedly if approximately 60 continuous upward steps are not available. The intervention will be completed in participants' usual daily environments, such as home, work, or campus.

Participants will wear a continuous glucose monitor during the intervention period and will complete activity, dietary, and study-related logs. After the two-week intervention, participants will repeat the standardized meal challenge and laboratory assessments.

The primary study outcomes include changes in postprandial glucose response, glycemic variability, and aerobic fitness from baseline to post-intervention. Secondary outcomes include changes in body composition, waist circumference, anaerobic power, and muscular strength. Exploratory outcomes include adherence and feasibility of the stair-climbing intervention.

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Hossein Rafiei, PhD, RD; Phone Number: 314-977-8675; Email: hossein.rafiei@health.slu.edu

Study Locations

• United States
  • Missouri
    • St Louis, Missouri, United States, 63104
      • Recruiting
      • Saint Louis University
      • Contact: Hossein Rafiei, PhD RD; Phone Number: 314-977-8675; Email: hossein.rafiei@health.slu.edu
      • Principal Investigator: Hossein Rafiei, PhD, RD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 18-35 years and able to provide informed consent.
• Body mass index (BMI) 25.0-34.99 kg/m² and otherwise healthy, without chronic disease.
• Sedentary or low-active lifestyle, defined as no regular structured exercise ≥3 days/week for ≥30 minutes per session during the past 3 months.
• Access to a safe staircase that permits completion of approximately 60 total stair steps per exercise bout. Approximately 60 upward steps are preferred when available; one or more flights may be used repeatedly if needed.
• No contraindications or increased-risk findings identified on the PAR-Q+ or health history screening.

Exclusion Criteria:

• Known cardiovascular, pulmonary, metabolic, renal, neurological, or musculoskeletal disease, or signs or symptoms suggesting increased risk during vigorous exercise, including diagnosed diabetes mellitus, cardiovascular disease, uncontrolled hypertension, chronic pulmonary disease, kidney disease, fainting or unexplained dizziness during exercise, chest pain with exertion, or severe shortness of breath with mild-to-moderate activity.
• Current use of medications that may affect exercise tolerance, heart-rate response, balance, glucose metabolism, or safety during vigorous exercise, including insulin or other glucose-lowering medications, beta-blockers, anti-arrhythmic medications, systemic corticosteroids, or medications that may cause dizziness, impaired balance, or altered exercise response.
• Orthopedic or joint conditions that could be aggravated by repeated stair climbing.
• Allergy, intolerance, dietary restriction, or other condition preventing safe consumption of the standardized meal replacement shake.
• Pregnancy or plans to become pregnant during the study period.
• Any other medical or psychological condition that, in the investigator's judgment, could make adherence difficult or place the participant at risk.
• Individuals currently enrolled in a course taught by the PI or other study personnel, or who are directly supervised, graded, or formally evaluated by a member of the study team.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Two-Week Stair-Climbing Exercise Snacks; Participants will complete a two-week stair-climbing exercise snack intervention. They will perform approximately 6-8 brief stair-climbing bouts per day for approximately 14 days. Each bout will include approximately 60 total stair steps completed at a self-selected challenging but safe pace. Participants will otherwise be asked to maintain their usual diet and lifestyle and avoid beginning a new exercise or diet program during the study.

Behavioral: Stair-Climbing Exercise Snacks; Participants will perform brief stair-climbing exercise snacks 6-8 times per day for 14 days. Each bout will consist of approximately 60 total stair steps completed at a self-selected challenging but safe pace. When possible, participants will complete approximately 60 upward steps. If 60 continuous upward steps are not available, participants may use one or more flights repeatedly by ascending and descending carefully until approximately 60 total steps are completed. The intervention will be completed independently in participants' usual daily environments, such as home, work, or campus. Participants will be instructed to use the handrail when needed, descend slowly and carefully, and not run down the stairs.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in 2-Hour Postprandial Glucose Area Under the Curve (AUC)	Postprandial glucose response will be assessed using continuous glucose monitoring during a standardized meal challenge performed before and after the two-week stair-climbing intervention. Glucose area under the curve (AUC) over the approximately 2-hour post-meal period will be calculated using the trapezoidal method and compared between pre- and post-intervention assessments.	Baseline (Day 1) and post-intervention (Day 15)
Change in CGM-Derived Glucose Standard Deviation	Glucose standard deviation will be calculated from continuous glucose monitoring data over three complete 24-hour periods during the early and late intervention periods and compared within participants.	Early intervention (Days 2-4) and late intervention (Days 11-13)
Change in Aerobic Capacity (VO₂max or Estimated VO₂max)	Aerobic capacity will be assessed using a VO₂max or estimated VO₂max test with metabolic cart analysis/indirect calorimetry during a graded exercise test. Peak oxygen uptake will be expressed in mL/kg/min and compared between baseline and post-intervention assessments. If a maximal test is not appropriate or feasible, a submaximal test with VO₂ extrapolation may be used.	Baseline (Day 0) and post-intervention (Day 15)
Change in CGM-Derived Glucose Coefficient of Variation	Glucose coefficient of variation will be calculated from continuous glucose monitoring data over three complete 24-hour periods during the early and late intervention periods and compared within participants.	Early intervention (Days 2-4) and late intervention (Days 11-13)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Body Weight	Body weight will be measured using the InBody 380 bioelectrical impedance analysis (BIA) system and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Body Fat Percentage	Total body fat percentage will be assessed using the InBody 380 bioelectrical impedance analysis (BIA) system and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Fat Mass	Total body fat mass will be assessed using the InBody 380 bioelectrical impedance analysis (BIA) system and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Lean Mass	Total lean mass will be assessed using the InBody 380 bioelectrical impedance analysis (BIA) system and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Phase Angle	Phase angle will be assessed using the InBody 380 bioelectrical impedance analysis (BIA) system and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Waist Circumference	Waist circumference will be measured using a measuring tape at the iliac crest and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Wingate Peak Power	Peak anaerobic power will be assessed during a 30-second Wingate anaerobic test performed on a cycle ergometer and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Wingate Mean Power	Mean anaerobic power will be assessed during a 30-second Wingate anaerobic test performed on a cycle ergometer and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Handgrip Strength	Handgrip strength will be measured using an InBody handgrip dynamometer. The best of three trials for each hand will be recorded, with dominant-hand grip strength used for the primary comparison between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in Segmental Body Fat Percentage	Segmental body fat percentage will be assessed using the InBody 380 bioelectrical impedance analysis (BIA) system and compared between baseline and post-intervention assessments.	Baseline (Day 0) and post-intervention (Day 15)
Change in 24-Hour Mean Glucose	Mean glucose will be calculated from continuous glucose monitoring data over prespecified early- and late-intervention periods and compared within participants.	Early intervention (Days 2-4) and late intervention (Days 11-13)
Change in Time in Range	The percentage of CGM readings within the prespecified glucose target range will be calculated over early- and late-intervention periods and compared within participants.	Early intervention (Days 2-4) and late intervention (Days 11-13)

Collaborators and Investigators

• Sponsor: St. Louis University
• Investigators: Principal Investigator: Hossein Rafiei, PhD, RD, St. Louis University

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: September 24, 2026
• First Submitted That Met QC Criteria: September 24, 2026
• First Posted (Actual): September 30, 2026

Study Record Updates

• Last Update Posted (Actual): September 30, 2026
• Last Update Submitted That Met QC Criteria: September 24, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Physical Activity; Obesity; Continuous Glucose Monitoring; Overweight; Body Composition; Cardiorespiratory Fitness; Glycemic Variability; Postprandial Glucose; Metabolic Health; Exercise Snacks; Anaerobic Power; Stair Climbing
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Pathological Conditions, Signs and Symptoms; Behavior; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity; Motor Activity
• Other Study ID Numbers: STUDY00000657

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

IPD Plan Description

Individual participant data will not be shared with researchers outside the study team, in accordance with the IRB-approved protocol and informed consent. Study findings may be disseminated in aggregate form through scientific presentations and peer-reviewed publications.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No