The Effect of Velocity Training in Functionally Limited Elderly

Aging Clinical Trial

Official title:

High Velocity Resistance Training in Older Men and Women

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01211496
• Other study ID #: 1042318
• Secondary ID: R03AG025141-01
• Status: Completed
• Phase: N/A
• First received: December 2, 2008
• Last updated: October 3, 2016
• Start date: June 2004
• Est. completion date: May 2008

Study information

• Verified date: October 2016
• Source: University of Missouri-Columbia
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

We are exploring a unique weight-training program for men and women 65 years or older that emphasizes high speed training. We believe that the speed at which muscles move may be more important to the performance of functional tasks than how strong the muscles are. We are comparing velocity training with traditional strength training to determine which method has the greatest effects on muscle strength, speed of movement, functional performance and physical disability. We believe that higher speed training will improve these measures to a greater extent than simply training for increased muscle strength.

Aging also results in loss of bone mass, which increases the risk for falls and fractures. Strength training also has been shown to maintain bone mass in the elderly, but no studies have examined high velocity resistance training and maintenance of bone mass. We believe it is important to examine this aspect of velocity training before recommendations can be made.

Description:

The study compared 12 weeks of explosive high-speed power training with traditional slow-speed strength training. Outcome measures included muscle performance: leg press (LP) and knee extension (KE) one-repetition maximum (1RM) and LP peak power (PP), velocity at peak power (PPV) and force at peak power (PPF) from 40%-90% of the 1RM. Measures of function consisted of habitual and maximal gait velocity, the short physical performance battery (SPPB), forward tandem walk, and lower limb movement time (braking speed) on an automobile driving simulator.

Participants reported to the laboratory for 2 weeks of baseline measurements. On visit 1, subjects were explained the study and completed an informed consent document. On visit 2 and 3, muscle performance and functional measures were obtained. The following week, all muscle performance and functional measures were repeated to establish reliability. At the end of baseline testing, participants were randomized to treatment. Following the 12-week RT intervention, post-training muscle performance and functional measures were obtained.

Resistance Training Protocol. Volunteers randomized into high-speed power training (HSPT) and slow-speed strength training (SSST) exercised 3 times per week for 12 weeks using computer-interfaced Keiser a420 pneumatic leg press and knee extension RT equipment (Fresno, CA). For HSPT, each training session consisted of 3 sets of 12-14 repetitions at 40%1RM. Participants performed an explosive movement at high speed during the concentric phase of each repetition, paused for one-second, and performed the eccentric portion of the contraction over 2 seconds. Volunteers randomized into SSST also exercised 3 times per week for 12 weeks with each training session consisting of 3 sets of 8-10 repetitions at 80%1RM. The participants performed each movement at a slow velocity (2 s for concentric phase of the repetition), paused for one second, and performed the eccentric portion of the contraction over 2 seconds. CON met three times a week for warm-up and stretching exercises, but performed no RT. HSPT and SSST participated in the same warm-up and stretching exercises as CON.

Measures Maximal strength and power. Leg press and seated knee extension 1RM were obtained using Keiser pneumatic RT equipment fitted with a420 electronics. The seat of both the recumbent LP and KE apparatus was positioned to place the hip and knee joints between 90 and 100 degrees of flexion. The 1RM was obtained by progressively increasing resistance until the subject was no longer able to push out one repetition successfully. The Borg Scale was used to assist in evaluating when 1RM (combined with perceived maximal effort) was reached. Peak muscle power was obtained at 40%, 50%, 60%, 70%, 80% and 90% of the 1RM approximately 30 minutes after 1RM testing (8,9). Participants were instructed to exert "as fast as possible" at each relative percentage of the 1RM. Three attempts were made at each resistance and the greatest PP output obtained at each resistance was used in the analysis. The corresponding PPV and PPF were obtained for each external resistance from 40%-90% 1RM. The 1RM was measured bi-weekly in HSPT and SSST only and relative training intensity was adjusted accordingly to ensure adequate overload during training. Post-training muscle performance measures were obtained using loads relative to the initial baseline 1RM as well as the post-training 1RM.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 52
• Est. completion date: May 2008
• Est. primary completion date: May 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 65 Years and older

Eligibility

Inclusion Criteria:

• 65 years of age

• relatively inactive

• male or female

• good overall health

• living independently (not in a nursing home or care facility)

Exclusion Criteria:

• physically active/athletic

• heart attack or unstable angina within 6 months of consent

• hip fracture, knee or hip replacement within 6 months of consent

• diagnosed neurological disease

• pulmonary disease requiring use of oxygen

• osteoarthritis of the knee

• severe visual or hearing impairment

Study Design

Allocation: Randomized, Intervention Model: Factorial Assignment, Masking: Single Blind (Investigator), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Aging

Intervention

Behavioral:
• High-speed power training
High speed resistance training, 3 sessions per week for 12 weeks
• Slow-speed strength training
Slow speed resistance training, 3 sessions per week for 12 weeks

Locations

Country	Name	City	State
n/a

Sponsors (2)

Lead Sponsor	Collaborator
University of Missouri-Columbia	National Institute on Aging (NIA)

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Strength and Power	The strength and power of the lower limb muscles will be measures using Keiser pneumatic leg press and knee extension exercise machines. The Keiser machines allow for the specific measurement of the contributions of force and velocity to the development of power, which will reveal whether the high-speed training protocol impacts speed-related measures of muscle performance.	6 months	Yes
Secondary	Mobility and Function	Walking speed tests (habitual gait speed and maximal gait speed), balance (tandem walk), stair climbing performance, chair rise time, and the timed up and go test will be used as overall measures of mobility and function.	6 months	No