Effects of Different Power Training Intensities in Older Adults

Adaptations Due to Different Intensities of Power Training on Neuromuscular Performance, Muscle Thickness and Functional Capacity in Elderly People: A Randomized Clinical Trial

Power (strength × velocity) is a crucial component for maintaining independence during aging. Therefore, investigating interventions aimed at improving this physical capacity is essential for this population. The aim of this study is to examine the effects of power training (PT) performed at low to moderate intensity (PTLM; 40-60% of 1-repetition maximum [1RM]) and moderate to high intensity (PTMH; 65-80% of 1RM) on muscle power, kinematic gait parameters, strength, muscle thickness, and functional performance in older adults. Participants will be randomly assigned to perform PTLM and PTMH. Data collection will occur before and after familiarization, as well as at weeks 8 and 16 of the training programs. Participants will undergo a series of tests in the following sequence: 1) muscle thickness and 1RM test; 2) muscle power, maximum voluntary contraction, and rate of force development; 3) functional performance. The primary analyses will be conducted on an intention-to-treat basis, comparing the effects of the interventions and groups over time. Generalized Estimating Equations (GEE) will be used, considering the factors of group (2 levels) and time (3 levels). Paired comparisons will be assessed using the Bonferroni post-hoc test to identify significant differences between groups and time points. All tests will be performed using JASP software (version 0.16.4.0), with statistical significance set at p < 0.05 for all analyses.

Study Overview

• Status: Enrolling by invitation
• Conditions: Investigating the Effects of Power Training in the Elderly
• Intervention / Treatment: Device: low to moderate intensity (PTLM; 40-60% of 1-repetition maximum [1RM]); Device: Moderate to high intensity (PTMH; 65-80% of 1-repetition maximum [1RM]) )

• Study Type: Interventional
• Enrollment (Estimated): 70
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • RS
    • Porto Alegre, RS, Brazil, 91410-070
      • Universidade Federal do Rio Grande do Sul (UFRGS)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion criteria:

• Age 60 years or older
• No participation in regular and systematic resistance training in the last three months
• No absolute or relative contraindications to exercise
• No musculoskeletal injuries that could interfere with training and assessments

Exclusion criteria:

• Use of steroids, nutritional supplements, or ergogenic substances
• Failure to complete all study phases
• Failure to complete more than 80% of the training sessions (32 sessions)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Low to moderate intensity (PTLM; 40-60% of 1-repetition maximum [1RM]); Power training performed at maximum velocity in the concentric phase with lower to moderate intensity	Device: low to moderate intensity (PTLM; 40-60% of 1-repetition maximum [1RM]); Power training performed at maximum velocity in the concentric phase with lower to moderate intensity; Other Names: Ultrasound; Linear Encoder; Load Cell; 1-Repetition Maximum (1RM); PTLM
Active Comparator: Moderate to high intensity (PTMH; 65-80% % of 1-repetition maximum [1RM]); Power training performed at maximum velocity in the concentric phase with moderate to high intensity	Device: Moderate to high intensity (PTMH; 65-80% of 1-repetition maximum [1RM]) ); Power training performed at maximum velocity in the concentric phase with moderate to high intensity; Other Names: Ultrasound; PTMH; Linear Encoder; Load Cell; 1-Repetition Maximum (1RM)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle Power	The power output during strength exercises is assessed using an encoder linear at two different intensities: 30% and 70% of 1RM in leg extension and leg press 45. Power output is the ability to generate force quickly and is a key measure of explosive strength. These tests are performed using different resistance levels to assess power across a range of intensities. Measurement Tool: Encoder linear (linear encoder or velocity-based device) Scale: Power output in watts (W) Higher scores indicate better power performance at each intensity.	Pre- and post-intervention (16 weeks of training)
Muscle Strength	Muscle strength is the ability of a muscle or muscle group to generate force against resistance. It reflects the maximum force that can be produced in a single effort and is essential for daily activities and overall physical function. One Repetition Maximum (1RM) is used to quantify maximal strength. Measurement Tool: 1RM testing Scale: 1RM (measured in kg) Higher scores indicate better strength performance.	Pre- and post-intervention (16 weeks of training)
Rate of Force Development	Rate of force development refers to the speed at which force is generated by a muscle or muscle group. It is a critical measure of neuromuscular performance, especially in activities that require explosive strength or rapid reactions. RFD is measured during maximal voluntary contractions. Measurement Tool: Load Cell Scale: Measured in Newtons per second (N/s) Higher scores indicate better neuromuscular performance.	Pre- and post-intervention (16 weeks of training)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional Capacity	Functional capacity refers to an individual's ability to perform activities required for daily living, such as walking, climbing stairs, or carrying objects. It reflects overall physical function and is often used to assess health status, particularly in older adults or clinical populations. The following tests were selected to assess functional capacity: Stair Climbing Test Scale: Total time to climb and descend a predetermined number of stairs. Shorter time indicates better performance. Timed Up and Go (TUG) Scale: Total time in seconds. Shorter time indicates better mobility and agility. 6-Meter Walk Speed Test Scale: Total time to walk 6 meters (seconds). Shorter time indicates faster walking speed. Sit-to-Stand Test (5 times) Scale: Total time to complete the 5 repetitions. Shorter time indicates better muscle strength and functional capacity.	Pre- and post-intervention (16 weeks of training)
Muscle hypertrophy	Muscle thickness is an indicator of muscle size and hypertrophy. It reflects the structural adaptations that occur in response to training. Ultrasound is used to measure the thickness of muscles such as the quadriceps, biceps, and triceps. Measurement Tool: Ultrasound imaging Scale: Muscle thickness in millimeters (mm) Higher scores indicate greater muscle hypertrophy.	Pre- and post-intervention (16 weeks of training)
Cognitive Capacity	The Montreal Cognitive Assessment (MoCA) is a brief screening tool used to assess cognitive function. It evaluates multiple cognitive domains, including memory, attention, language, and executive functions. It is commonly used to assess cognitive decline or impairments. Measurement Tool: MoCA test Scale: MoCA score ranges from 0 to 30, with higher scores indicating better cognitive function. Higher scores indicate better cognitive function.	Pre- and post-intervention (16 weeks of training)

Collaborators and Investigators

• Sponsor: Federal University of Rio Grande do Sul

Publications and helpful links

General Publications

• Martinikorena I, Martinez-Ramirez A, Gomez M, Lecumberri P, Casas-Herrero A, Cadore EL, Millor N, Zambom-Ferraresi F, Idoate F, Izquierdo M. Gait Variability Related to Muscle Quality and Muscle Power Output in Frail Nonagenarian Older Adults. J Am Med Dir Assoc. 2016 Feb;17(2):162-7. doi: 10.1016/j.jamda.2015.09.015. Epub 2015 Nov 11.
• Mc Dermott EJ, Balshaw TG, Brooke-Wavell K, Maden-Wilkinson TM, Folland JP. Fast and ballistic contractions involve greater neuromuscular power production in older adults during resistance exercise. Eur J Appl Physiol. 2022 Jul;122(7):1639-1655. doi: 10.1007/s00421-022-04947-x. Epub 2022 Apr 16.
• Bandeira-Guimaraes M, Blanco-Rambo E, Vieira AF, Saez de Asteasu ML, Pinto RS, Izquierdo M, Cadore EL. Chronic Effects of Different Intensities of Power Training on Neuromuscular Parameters in Older People: A Systematic Review with Meta-analysis. Sports Med Open. 2023 Oct 24;9(1):98. doi: 10.1186/s40798-023-00646-9.
• de Vos NJ, Singh NA, Ross DA, Stavrinos TM, Orr R, Fiatarone Singh MA. Optimal load for increasing muscle power during explosive resistance training in older adults. J Gerontol A Biol Sci Med Sci. 2005 May;60(5):638-47. doi: 10.1093/gerona/60.5.638.

Helpful Links

• Related Info
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Study record dates

Study Major Dates

• Study Start (Actual): April 2, 2025
• Primary Completion (Estimated): December 11, 2025
• Study Completion (Estimated): December 11, 2025

Study Registration Dates

• First Submitted: May 23, 2025
• First Submitted That Met QC Criteria: June 7, 2025
• First Posted (Actual): June 15, 2025

Study Record Updates

• Last Update Posted (Actual): June 15, 2025
• Last Update Submitted That Met QC Criteria: June 7, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: muscle strength; Aging; functional capacity; resistance training; muscle hypertrophy
• Other Study ID Numbers: 85503024.6.0000.5347

Plan for Individual participant data (IPD)

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

Drug and device information, study documents

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