Physical Inactivity, Sedentary Behavior, Cardiometabolic Health
Conditions
Keywords
exercise snacking, physical activity, aerobic fitness, behavioral intervention, exercise motivation, physical activity maintenance, randomized controlled trial
Brief summary
Regular physical activity is associated with numerous health benefits, yet many young adults do not achieve recommended levels of physical activity. Exercise snacking, which involves performing brief bouts of physical activity throughout the day, may provide a practical alternative to traditional exercise programs by making physical activity easier to incorporate into daily routines. This randomized controlled trial will evaluate whether a 12-week exercise snacking intervention improves physical activity levels, aerobic fitness, cardiometabolic health, and psychological well-being in insufficiently active young adults. Participants will be randomly assigned to either an exercise snacking intervention or a usual behavior control group. Assessments will be completed at baseline, after the 12-week intervention, and after an additional 12-week follow-up period to determine whether any changes are maintained after the intervention ends. The study will measure physical activity using wearable activity monitors and assess aerobic fitness, body composition, blood pressure, blood lipids, glucose, exercise motivation, affective responses to exercise, and mental well-being. The findings will help determine whether exercise snacking is an effective and sustainable strategy for improving health in young adults and may inform future physical activity recommendations and interventions
Detailed description
Regular physical activity reduces the risk of cardiovascular disease, type 2 diabetes, obesity, and other chronic health conditions. Despite these well-established benefits, many young adults do not achieve recommended levels of physical activity. Commonly reported barriers include limited time, competing academic or work demands, and difficulty maintaining structured exercise programs. Exercise snacking, defined as accumulating multiple brief bouts of moderate-to-vigorous physical activity throughout the day, has emerged as a potential strategy for increasing physical activity while minimizing many of the barriers associated with traditional exercise programs. Although short bouts of physical activity have demonstrated favorable acute physiological effects, relatively few randomized controlled trials have evaluated whether exercise snacking produces sustained improvements in objectively measured physical activity, physical fitness, cardiometabolic health, and psychological outcomes in free-living young adults. The purpose of this study is to determine whether a 12-week exercise snacking intervention improves physical activity behavior, aerobic fitness, cardiometabolic health, exercise motivation, affective responses to physical activity, and psychological well-being compared with a usual behavior control group. Participants will be randomly assigned to either an exercise snacking intervention or a control condition. Following completion of the intervention, participants will be observed for an additional 12 weeks to evaluate the maintenance of behavioral and physiological changes after structured support is withdrawn. The primary objectives are to determine whether exercise snacking increases objectively measured physical activity and improves aerobic fitness. Secondary objectives are to evaluate changes in body composition, blood pressure, fasting cardiometabolic biomarkers, exercise motivation, affective responses to exercise, and psychological well-being. Exploratory analyses will examine whether changes in motivation and affective responses are associated with long-term maintenance of physical activity during the follow-up period. This study will contribute to the growing evidence regarding practical, scalable approaches for increasing physical activity among young adults and may help inform future lifestyle interventions and public health recommendations aimed at promoting long-term engagement in regular physical activity
Interventions
BEHAVIORALExercise Snacking
Participants assigned to the intervention group will complete multiple brief bouts of moderate-to-vigorous physical activity throughout each day for 12 weeks. Each exercise snack will typically last approximately 1-3 minutes and may include activities such as stair climbing, brisk walking, repeated sit-to-stands, body-weight squats, or other moderate-to-vigorous activities that can be incorporated into daily routines. Participants will receive standardized written instructions, examples of exercise snacks, and periodic follow-up visits to monitor adherence and reinforce study procedures.
Sponsors
University of Wisconsin, River Falls
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Age 18-60 years. * Body mass index (BMI) ≥18.5 kg/m². * Insufficiently physically active, defined as generally not meeting current physical activity guidelines for moderate-to-vigorous physical activity. * Able to safely participate in moderate-to-vigorous physical activity as determined by study screening procedures, including completion of the Physical - Activity Readiness Questionnaire (PAR-Q+) and health history review. * Willing and able to provide written informed consent. * Willing to complete all study visits, wear activity monitors, and comply with study procedures.
Exclusion criteria
* Known cardiovascular, pulmonary, metabolic, neurological, orthopedic, or other medical conditions that would make participation in moderate-to-vigorous physical activity unsafe. * Resting heart rate \>100 beats/minute at screening. * Resting blood pressure \>160/100 mmHg at screening. * Clinically significant electrocardiogram (ECG) abnormalities identified during screening that require medical evaluation. * Current participation in regular structured physical activity that meets or exceeds recommended physical activity guidelines. * Physical limitations or injuries that preclude safe participation in the intervention or fitness testing. * Moderate-to-severe psychological distress or other mental health concerns identified during screening that require referral or would make study participation inappropriate. * Pregnancy or any other condition judged by the investigators to make participation unsafe or interfere with completion of study procedures.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Moderate-to-Vigorous Physical Activity | Baseline, Week 12, and Week 24 | Average daily minutes of moderate-to-vigorous physical activity measured objectively using an accelerometer worn for seven consecutive days. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body Fat Percentage | Baseline, Week 12, Week 24 | Body composition measured using air displacement plethysmography (BodPod). |
| Aerobic Fitness | Baseline, Week 12, and Week 24 | Aerobic fitness assessed during a submaximal cycle ergometer exercise test with respiratory gas analysis using a metabolic measurement system. |
| Fasting Blood Glucose | Baseline, Week 12, Week 24 | Capillary fasting glucose measured using the Cholestech LDX analyzer. |
| Blood Lipid Profile | Baseline, Week 12, Week 24 | Total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides measured from fasting capillary blood samples. |
| Exercise Motivation | Baseline, Week 12, Week 24 | Exercise motivation will be assessed using the 24-item Behavioral Regulation in Exercise Questionnaire-3 (BREQ-3). The questionnaire produces six subscale scores: amotivation, external regulation, introjected regulation, identified regulation, integrated regulation, and intrinsic regulation. Each subscale is calculated as the mean of four items and ranges from 0 to 4. Higher scores indicate a greater degree of the corresponding type of exercise motivation; therefore, higher scores do not uniformly represent a better or worse outcome. |
| Psychological Well-Being | Baseline, Week 12, Week 24 | Psychological well-being will be assessed using the World Health Organization-Five Well-Being Index (WHO-5). The five items are summed to produce a raw total score ranging from 0 to 25. Higher scores indicate better psychological well-being. |
| Depressive Symptoms | Baseline, Week 12, Week 24 | Depressive symptoms will be assessed using the 9-item Patient Health Questionnaire (PHQ-9). Items are summed to produce a total score ranging from 0 to 27. Higher scores indicate more severe depressive symptoms and therefore a worse outcome. |
| Anxiety Symptoms | Baseline, Week 12, Week 24 | Anxiety symptoms will be assessed using the 7-item Generalized Anxiety Disorder scale (GAD-7). Items are summed to produce a total score ranging from 0 to 21. Higher scores indicate more severe anxiety symptoms and therefore a worse outcome. |
| Perceived Stress | Baseline, Week 12, Week 24 | Perceived stress will be assessed using the 10-item Perceived Stress Scale (PSS-10). Items are summed after reverse-scoring the positively stated items, producing a total score ranging from 0 to 40. Higher scores indicate greater perceived stress and therefore a worse outcome. |
Countries
United States
Contacts
CONTACTGregory Ruegsegger, PhD
CONTACTRicky Lopez, MS
PRINCIPAL_INVESTIGATORGregory Ruegsegger, PhD
University of Wisconsin, River Falls
Outcome results
None listed