OBJECTIVE

This study examined the combined effects of unstable resistance training (URT) and high-definition transcranial direct current stimulation (tDCS) on proprioception, balance, and fall risk in community-dwelling older adults, targeting both central neural drive and peripheral neuromuscular adaptations.

METHOD

Ninety older adults (mean age 66.2 ± 3.3 years) were recruited and randomly assigned to five groups: (1) URT + a-tDCS, (2) URT + s-tDCS, (3) URT, (4) stable resistance training (SRT) and (5) a health education control group (HALE). All participants underwent an 8-week intervention (three sessions per week, 30 min per session). Participants in the URT + a-tDCS group received 2 mA stimulation for 20 min concurrently with URT sessions. Assessments of ankle proprioception, balance and fall risk were conducted at baseline and post-intervention.

RESULT

Eight weeks of URT + a-tDCS significantly improved proprioception at dorsiflexion and plantarflexion, compared with URT + s-tDCS, URT, SRT and baseline (P < 0.05). URT + s-tDCS and URT enhanced proprioception at plantarflexion than baseline (P = 0.033; P = 0.021). Balance measurements (i.e. COP displacement, COP ellipse area and sway velocity index) under stable and unstable surfaces were significantly improved after URT + a-tDCS, compared with other three training modalities and baseline. The fall-risk declined significantly after URT + a-tDCS compared with HALE and baseline (P < 0.05). The change in sway velocity index was positively related to the change in proprioception at plantarflexion after 8-week URT intervention (R2 = 0.378, P = 0.015).

CONCLUSION

The combined URT and a-tDCS intervention demonstrated synergistic effects, producing statistically significant improvements in proprioceptive acuity and balance parameters among older adults. This integrated intervention offers a promising approach to fall prevention and highlights the importance of targeting both central and peripheral mechanisms in rehabilitation strategies.

Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.

Improvement of balance along with bone-enhancing pharmacotherapy can improve the level of an individual's physical activity and mobility. Balance can be improved with enhancement of postural proprioception and muscular strength. Postural deformities have been shown to impair quality of life of osteoporotic individuals. Kyphotic posture has been demonstrated to contribute to propensity to fall in osteoporotic individuals. Kyphotic posturing and gait disorders can be managed through proprioceptive training, use of a weighted kypho-orthosis, muscle re-education, and safe resistance exercises. Proprioceptive balance training can reduce falls and fracture. Sarcopenia and osteoporotic fractures create musculoskeletal challenges that cannot be met with pharmacotherapy alone. Bone loss, imbalance, and gait disorder along with cognitive concerns can increase with aging. Even in healthy persons, predisposition to falls increases with age-related neuromuscular changes. Muscle strength decreases approximately 50% from age 30 to 80. Furthermore, the amount of body sway increases with reduction of proprioception. Therefore, measures that can decrease imbalance can reduce the risk for falls and fracture. In normal balance, ankle strategies are recruited rather than hip strategies. Strengthening of the lower extremity muscles reduces the risk for falls. Gait aids can also decrease the risk for falls. During a fall, the risk for hip fracture increases 30-fold if there is direct impact to the hip. The use of hip protectors can decrease the risk for hip fracture during a sideways fall. Training in effective safe-landing strategies should be included in fall prevention programs.

To reduce the number of falls in old age, we need to understand the mechanisms underpinning a fall, who are at risk of falling, and what interventions can prevent such individuals from falling. This paper provides an overview of our recent research on tripping and muscle strength in the elderly, addressing these questions. To prevent a fall after tripping over an obstacle, high demands are posed on lower limb muscles. It was shown that the support limb plays an important role in balance recovery by generating the appropriate joint moments during push-off. Older individuals show lower rates of moment generation in all support limb joints and a lower peak ankle moment than young adults. As strength declines with age (due to muscular, tendinous and neural alterations), leg muscle strength might be the limiting factor in preventing a fall. Indeed, high-risk fallers could be identified based on maximum leg press push-off force capacity. Resistance training can reverse the ageing-related loss of strength. Therefore, the effects of 16-weeks resistance training on tripping reactions were studied in a small group of elderly. Maximum push-off force increased significantly by training. Moreover, trainers improved more than controls in moment generation after tripping, especially around the ankle. It can be concluded that transfer of resistance training effects to balance recovery is feasible.

BACKGROUND

Ankle foot orthoses (AFO) are commonly used orthotic device in order to restore the ankle foot function and to improve the balance and gait in post-stroke hemiparetic patients. However, there remain some discussions about their effectiveness on long term hemiparetic patients who had mild to moderate spasticity.

AIM

To investigate the relative effect of prefabricated thermoplastic posterior leaf spring AFO (PLS-AFO) on balance and fall risk.

DESIGN

A cross-over interventional study

SETTING

The Department of PMR of a tertiary hospital.

POPULATION

Twenty-five chronic post-stroke long duration hemiparetic patients who had Ashworth grade 1-2 spasticity at affected calf muscles and lower limb Brunnstrom stage 2-3 and also able to walk independently without an assistive device.

METHODS

Berg Balance Scale (BERG), and the postural stability test (PST) and the fall risk test (FRT) of Biodex balance systems were used for the assessments. All of the patients were assessed with AFO and without AFO. All assessments were made with footwear.

RESULTS

The mean post-stroke duration was 20,32±7,46 months. The BERG scores were 42,12±9,05 without AFO and 47,52±7,77 with AFO; the overall stability scores of FRT were 3,35±1,97 without AFO and 2,69±1,65 with AFO (P<0,001).

CONCLUSION

It was found that the prefabricated thermoplastic PLS-AFO improve balance and provide fall risk reduction in chronic post-stroke ambulatory hemiparetic patients who had mild to moderate spasticity on their affected lower limb.

CLINICAL REHABILITATION IMPACT

These results encourage the usage of AFO on long duration hemiparetic patients in order to provide better balance and lesser fall risk.