The Effects of Exercise Snacks on Endothelial Function and Body Composition in Overweight Individuals

Overview

This randomized controlled trial investigates the effects of two types of stair-climbing exercise snacks versus moderate-intensity continuous training on vascular health, body composition, and blood lipids in overweight or obese adults. Participants will be assigned to one of four groups for 6-8 weeks. The control group receives no exercise intervention. Primary outcomes include endothelial function (ultrasound), body composition (InBody), and lipid profile (blood test).

Detailed description

This is a parallel group randomized controlled trial, with the study subjects being overweight or obese adults (with a body mass index of ≥ 24 kg/m²). Participants will be recruited from universities and randomly assigned to one of the following four groups:

Short-term stair climbing exercise group Participants climbed the stairs 4 to 5 times a day, each time ascending 5 floors (approximately 1 minute each time). There was at least a 1-hour interval between each exercise session, and the exercises were carried out during daily activities. They exercised 3 to 5 times a week for 6 to 8 weeks.

Long-term stair climbing nutrition supplementation group The participants also conducted 4 to 5 stair climbing training sessions every day. Each training session consisted of 3 sets of climbing 5 floors (the total climbing height for each training session was 15 floors), with a rest period of no more than 1 minute between each set. The interval between two training sessions was no less than 1 hour. They exercised 3 to 5 times a week for 6 to 8 weeks.

Moderate-intensity continuous training group (MICT) Participants engaged in 30-minute moderate-intensity running (including warm-up and cool-down activities) each time, 3 to 5 times a week, for 6 to 8 weeks.

Control group Participants maintained their daily activities and did not receive any exercise intervention measures.

Result measurement indicators:

Vascular health: Assessing endothelial function through ultrasound measurement of flow-mediated vascular dilation (FMD).

Body composition: Measured using the InBody body bioelectrical impedance analyzer (including muscle mass, fat mass and body fat percentage).

Blood lipid test: Collect fasting blood samples and measure low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG), and total cholesterol (TC).

Measurement time points: Measurements were conducted at the baseline (at the beginning of the study), 3-4 weeks (during the intervention period), and 8 weeks (after the intervention ended).

This research protocol has been approved by the Institutional Review Board of Shandong Second Medical University. All participants are required to sign a written informed consent form.

Interventions

• Behavioral Short-term stair climbing exercise snack group
  Adopt a fragmented approach, climbing stairs 4-5 times a day, each time climbing 5 floors (approximately 1 minute per session), with at least 1 hour of interval between each session, and spread throughout the daily activity periods. Exercise 3-5 days per week for a total of 6-8 weeks.
• Behavioral Long-duration stair climbing exercise snack group
  On the basis of climbing stairs 4 to 5 times a day, increase the single exercise volume: complete 2 or 3 sets of climbing 5 floors of stairs each time (that is, the total number of floors climbed each time is 10 or 15), with no more than 1 minute of rest between sets. The intervals between each exercise should be at least 1 hour. Exercise 3 to 5 days a week, for a total of 6 to 8 weeks of intervention.
• Behavioral Moderate-intensity continuous exercise（MICT）
  Exercise 3 to 5 days per week for a total of 6 to 8 weeks. Perform 30 minutes of moderate-intensity running training every day.

Primary outcome measures

• Flow-mediated dilation (FMD, relative percentage) [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Body fat mass [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Time to peak dilation [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Basal brachial artery diameter [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Peak brachial artery diameter [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Absolute flow-mediated dilation (FMDabs) [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Standardized FMD [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Body weight [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Body fat percentage [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Body mass index (BMI) [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]

Secondary outcome measures (8)

• Systolic blood pressure (SBP) [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Serum high-density lipoprotein (HDL) cholesterol concentration [Time frame: Measured at baseline and post-intervention (after 6-8 weeks).]
• Diastolic blood pressure (DBP) [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Heart rate [Time frame: Measured at baseline, mid-intervention (approximately 3-4 weeks), and post-intervention (after 6-8 weeks).]
• Serum low-density lipoprotein (LDL) cholesterol concentration [Time frame: Measured at baseline and post-intervention (after 6-8 weeks).]
• Serum total cholesterol concentration [Time frame: Measured at baseline and post-intervention (after 6-8 weeks).]
• HDL/LDL cholesterol ratio [Time frame: Measured at baseline and post-intervention (after 6-8 weeks).]
• Serum triglyceride concentration [Time frame: Measured at baseline and post-intervention (after 6-8 weeks).]

Eligibility criteria

Inclusion criteria

• Age: 18-35 years old (male, female);
• Clear consciousness, stable vital signs;
• Able to understand and follow simple instructions;
• No regular exercise for at least 3 months;
• BMI ≥ 24 kg/m2.

Exclusion criteria

• There are other serious diseases, such as tumors;
• There are other neurological diseases;
• There are serious diseases that simultaneously affect the heart, liver, kidneys, endocrine system or hematopoietic system;
• There is a history of alcohol or drug abuse;
• Participated in other clinical trials that might affect the results of this study;
• There are other neurological or musculoskeletal diseases, with pain worsening with exercise;
• It is forbidden to engage in physical training.
• Within the past 3 months, there have been acute cardiovascular events such as acute myocardial infarction,unstable angina pectoris, severe arrhythmia, acute heart failure, etc.；
• Uncontrolled hypertension；
• Severe pulmonary diseases, such as uncontrolled asthma, acute exacerbation of chronic obstructive pulmonary disease, interstitial lung disease with significant exercise limitation；
• Severe joint and bone diseases, acute soft tissue injuries, fractures that have not healed, etc., making it impossible to complete the prescribed exercise load；
• Presence of bleeding tendencies, coagulation dysfunction, or within the past 1 month, there has been major bleeding or a history of surgery；
• The investigator judges that there are any other situations that may affect the safety of the subjects or the results of the trial.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Prevention

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07558421 · 2026YX160

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗