Falls are a leading cause of injury-related hospitalization among older women. Age-related declines in gait speed and postural stability are known risk-factors for falls. While exercise is well-known to help maintain or improve these losses, only 24.4% of older Canadian women are considered physically active.
Dance can act as a fun and social way to engage older women in exercise. Line dancing in particular has been shown to improve gait speed, knee extensor strength and endurance; however high doses are needed to achieve gains. Clifford and colleagues found that program lengths of 24 hours are needed to effect change, while Merome and colleagues recommend 3 hours per week. These high training doses may not be feasible for participants or community centres who offer programming. The time to commute to classes, find parking and caregiver roles at home are all cited as barriers to physical activity. We also propose that BFR could be a novel addition to increase the physiologic strain of online dance classes, which we hypothesize have a lower intensity and thereby lead to less fitness adaptations. Online classes are of interest as they can serve to reduce barriers to physical activity often experienced by older adults in Canada.
- We propose online dance classes have reduced efficacy in stimulating adaptations to gait speed, strength and endurance when compared to in-person classes.
- We propose blood flow restriction (BFR) as a novel addition to dance classes in order to aid in reaching physiological overload in more efficient time-frame.
BFR works by partially reducing blood flowing in and out of working muscles, thereby reducing oxygen availability, promoting anaerobic energy pathways and keeping metabolites in the muscles for a longer time period. Numerous studies have confirmed that when combined with low-intensity exercise BFR is capable of producing similar strength gains as high-intensity exercise. Additionally, BFR is safe and has been widely used among older adults and individuals with various medical conditions, including cardiovascular conditions.
While the benefits of BFR for muscle strength and hypertrophy have been greatly studied, there is limited research on its effects on gait and postural stability. Additionally, there is minimal research on potential combinations of BFR with dance-based activity.
- This study will examine the differences between online and in-person delivery of 90 minute line dance classes on the postural stability and gait of older females over 10-weeks.
- This study will then investigate the effects of combining BFR with 10-weeks of 90 minute line dancing classes for the postural stability and gait of older females.
Finally, muscle oxygenation and kinematic analysis will be conducted to help provide insight into any potential changes in gait and postural stability.
The intervention will consist of 10-weeks of line dancing classes, during which half the groups will be randomized to wear elasticized BFR bands pulled tight to a 7/10 of perceived pressure. Classes will be once per week for 90 minutes and will include a warm-up, 4 pre-set choreographies and a cool down. Breaks will be provided throughout the class.
Assessments will occur at pre, mid and post.
Gait will be assessed during a 6-minute walk test. During the test, participants will be filmed from a sagittal view to obtain kinematics. They will also be asked to wear a heart-rate monitor and muscle oxygenation sensors on their lower limbs.
Postural stability will be assessed via 30-seconds of quiet standing on force plates in conditions of eyes open, eyes closed and foam. Participants will also be asked to wear an accelerometer on their upper back during the assessment to obtain correlation to force plate data.
Functional strength will be assessed using 30-second sit to stand (with a secondary timer to obtain 5 time sit to stand length) and the Calf-Raise Senior test. Dynamic balance and mobility will be evaluated using the Functional Reach Test, and the Timed Up and Go in both single and dual-tasks. Aerobic capacity will be measured using a 3 minute Step Test while the participant wears a heart-rate monitor and muscle oxygenation sensors.
Finally scales of fears of falling, social connectedness, and overall mental health will be collected.
It is expected that this study will have great practical implications as the accessibility of this program can provide opportunities to older adults from various remote locations to increase their levels of physical activity in a safe manner. The affordability may also aid in adoption by community health and recreation centers as an easy-to-implement program that helps to improve the postural stability and gait of older women, thereby promoting independence and quality of life.