Regular physical activity is associated with enhanced plasticity in the motor cortex, but the effect of a single session of aerobic exercise on neuroplasticity is unknown. The aim of this study was to compare corticospinal excitability and plasticity in the upper limb cortical representation following a single session of lower limb cycling at either low or moderate intensity, or a control condition. We recruited 25 healthy adults to take part in three experimental sessions. Cortical excitability was examined using transcranial magnetic stimulation to elicit motor-evoked potentials in the right first dorsal interosseus muscle. Levels of serum brain-derived neurotrophic factor and cortisol were assessed throughout the experiments. Following baseline testing, participants cycled on a stationary bike at a workload equivalent to 57% (low intensity, 30 min) or 77% age-predicted maximal heart rate (moderate intensity, 15 min), or a seated control condition. Neuroplasticity within the primary motor cortex was then examined using a continuous theta burst stimulation (cTBS) paradigm. We found that exercise did not alter cortical excitability. Following cTBS, there was a transient inhibition of first dorsal interosseus motor-evoked potentials during control and low-intensity conditions, but this was only significantly different following the low-intensity state. Moderate-intensity exercise alone increased serum cortisol levels, but brain-derived neurotrophic factor levels did not increase across any condition. In summary, low-intensity cycling promoted the neuroplastic response to cTBS within the motor cortex of healthy adults. These findings suggest that light exercise has the potential to enhance the effectiveness of motor learning or recovery following brain damage.
1 July 2011 in Archives of Physical Medicine and Rehabilitation
Background and Purpose—: Regular physical activity (PA) is an important recommendation for stroke prevention. We compared the associations of self-reported PA with incident stroke in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. Methods—: REGARDS recruited 30 239 US blacks (42%) and whites, aged ≥45 years with follow-up every 6 months for stroke events. Excluding those with prior stroke, analysis involved 27 348 participants who reported their frequency of moderate to vigorous intensity PA at baseline according to 3 categories: none (physical inactivity), 1 to 3×, and ≥4× per week. Stroke and transient ischemic attack cases were identified during an average of 5.7 years of follow-up. Cox proportional hazards models were constructed to examine whether self-reported PA was associated with risk of incident stroke. Results—: Physical inactivity was reported by 33% of participants and was associated with a hazard ratio of 1.20 (95% confidence intervals, 1.02–1.42; P =0.035). Adjustment for demographic and socioeconomic factors did not affect hazard ratio, but further adjustment for traditional stroke risk factors (diabetes mellitus, hypertension, body mass index, alcohol use, and smoking) partially attenuated this risk (hazard ratio, 1.14 [0.95–1.37]; P =0.17). There was no significant association between PA frequency and risk of stroke by sex groups, although there was a trend toward increased risk for men reporting PA 0 to 3× a week compared with ≥4× a week. Conclusions—: Self-reported low PA frequency is associated with increased risk of incident stroke. Any effect of PA is likely to be mediated through reducing traditional risk factors.
Objective: The technique called Lee Silverman Voice Treatment (LSVT)-LOUD has previously been used to improve voice quality in people with Parkinson’s disease. The objective of this study was to assess the effectiveness of an alternate intervention, LSVT-BIG (signifying big movements), to improve functional mobility. Design: Systematic review with meta-analysis of randomized trials. Data sources: Medline, Embase, CINAHL, AgeLine, Scopus and Cochrane Library were searched from inception to September 2017 using multiple search terms related to Parkinson’s disease and LSVT-BIG. Review method: Two researchers searched the literature for studies of the LSVT-BIG intervention of 16 sessions, delivered by a certified instructor over four weeks, to any other intervention. Outcomes related to functional ability were included. Study quality was appraised using the Cochrane Risk of Bias tool. Results: Four studies were included, reporting on three randomized trials of 84 participants with mild Parkinson’s disease. Compared to physiotherapy exercises, or a shorter training protocol, there was a significant improvement in motor function assessed with the Unified Parkinson’s Disease Rating Scale part III (mean difference = −3.20, 95% confidence interval = −5.18 to −1.23) and a trend towards faster Timed Up and Go performance (mean difference = −0.47, 95% confidence interval = −0.99 to 0.06) and 10-metre walk test (mean difference = −0.53, 95% confidence interval = −1.07 to 0.01). Conclusion: Compared to shorter format LSVT-BIG or general exercise, LSVT-BIG was more effective at improving motor function. This provides preliminary, moderate quality evidence that amplitude-oriented training is effective in reducing motor impairments for people with mild Parkinson’s disease.
1 February 2018 in Archives of Physical Medicine and Rehabilitation