Effects of HIIT in Older Adults

NCT07170579 | Completed

• 1 other identifier: 2067313
• Study Type: interventional
• Target: 39
• Locations: 1 country
• Sites: 1

Brief Summary

This study investigated the effects of high-intensity interval training (HIIT) on functional fitness in older adults. As people age, they often experience a natural decline in physical abilities such as strength, flexibility, balance, and endurance, which can limit their ability to perform daily activities independently. Finding safe and effective exercise strategies to maintain or improve these abilities is critical for promoting healthy aging and preserving autonomy. In this study, older adults participated in a structured HIIT program adapted to their functional capacity. HIIT consists of short bursts of intense physical activity followed by periods of active rest. This type of training is known for improving cardiovascular and muscular fitness in a short period of time. Participants were assessed on various aspects of physical function before, during, and after the intervention. Tests included handgrip strength, upper and lower body strength, flexibility, aerobic endurance, and mobility. The results showed that HIIT significantly improved physical function in older adults, including increased muscle strength, flexibility, aerobic capacity, and agility. These findings suggest that HIIT can be a safe, efficient, and accessible option to promote health and independence in the aging population.

Conditions

Aging

Keywords

High-intensity interval training; functional fitness; older adults; aging; physical exercise; autonomy; activities of daily living

Outcome Measures

Primary Outcomes (1)

• Number of steps completed in the 2-Minute Step Test

  Number of steps completed in the 2-Minute Step Test The 2-Minute Step Test assesses aerobic endurance. Participants are instructed to march in place for two minutes, raising the knees to a target height midway between the kneecap and hip. The number of steps completed with the right knee reaching the target is counted.

  Baseline (Week 0), Mid-intervention (Week 33), and Post-intervention (Week 65)

Secondary Outcomes (6)

• Handgrip strength (kg)

  Baseline (Week 0), Mid-intervention (Week 33), and Post-intervention (Week 65)

• Upper body strength (Arm Curl Test)

  Baseline (Week 0), Mid-intervention (Week 33), and Post-intervention (Week 65)

• Lower body strength (30-Second Chair Stand)

  Baseline (Week 0), Mid-intervention (Week 33), and Post-intervention (Week 65)

• Upper body flexibility (Back Scratch Test)

  Baseline (Week 0), Mid-intervention (Week 33), and Post-intervention (Week 65)

• Lower body flexibility (Chair Sit-and-Reach Test)

  Baseline (Week 0), Mid-intervention (Week 33), and Post-intervention (Week 65)

Study Arms (2)

HIIT Group

EXPERIMENTAL

Participants perform high-intensity interval training (HIIT) sessions three times per week, including aerobic exercises with intervals of effort and recovery, adapted to older adults.

Other: Exercise

Control Group

NO INTERVENTION

Participants maintain their usual daily activities and do not receive any structured exercise intervention during the study period.

Interventions

Exercise OTHER

Participants engaged in High-Intensity Interval Training (HIIT) sessions three times per week, each lasting 60 minutes. Sessions included a 10-minute warm-up, a central HIIT block with cycles of aerobic exercises performed at high intensity (30-60 seconds) alternated with active recovery (60-90 seconds), followed by a 10-minute aerobic functional segment and a 10-minute cool-down with stretching. Exercises included modified jumping jacks, stationary marching, high knees, squats, and functional movements tailored to the participants' physical capacity. Training intensity was monitored using the Borg Rating of Perceived Exertion scale, targeting 13-17 during effort phases and 9-11 during recovery.

HIIT Group

Eligibility Criteria

• Age: 60 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Community-dwelling individuals aged 60 years or older
• Able to walk independently without assistive devices
• Sufficient cognitive ability to follow instructions and participate in assessments
• Medically stable and cleared for physical activity by a healthcare provider
• No current participation in structured exercise programs
• Willingness to participate in the intervention and attend scheduled assessments
• Provided written informed consent

You may not qualify if:

• Individuals younger than 60 years
• Severe musculoskeletal, cardiovascular, or neurological conditions that contraindicate physical exercise
• Uncontrolled hypertension or diabetes
• Recent surgery or hospitalization in the past 6 months
• Severe visual or auditory impairments that limit test performance
• Use of mobility aids (e.g., walker or cane for ambulation)
• Participation in another clinical trial simultaneously

Sponsors & Collaborators

• Instituto Politécnico de Bragança: lead

Study Sites (1)

Instituto Politécnico de Bragança

Bragança, 5300-253, Portugal

Location

MeSH Terms

Conditions

Motor Activity

Interventions

Exercise

Condition Hierarchy (Ancestors)

Behavior

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: August 28, 2025
• First Posted: September 12, 2025
• Study Start: April 1, 2024
• Primary Completion: June 15, 2025
• Study Completion: August 20, 2025
• Last Updated: September 12, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

PT (1)