5 RESEARCH ARTICLES
– Endurance exercise training improves cerebrovascular health and has neurotrophic effects within the hippocampus
– 12 master athletes (age ≥ 50 years) with long-term endurance training histories (≥15 years)
– cease all training and vigorous physical activity for 10 consecutive days
– Resting CBF significantly decreased in eight gray matter brain regions
– 188 community-dwelling older adults (53.7% female; 63.98±7.3 years)
– 7 day physical activity behaviour monitoring
– Light physical activity is associated with higher executive functioning in community-dwelling older adults
– This strengthens the evidence supporting exercise as a neuroprotective agent
– Gill SJ, et al
– A sample of 226 (52.2% female) community dwelling middle-aged and older adults (66.5±6.4 years) in the Brain in Motion Study, completed the Lifetime Total Physical Activity Questionnaire and underwent neuropsychological and cerebrovascular blood flow testing
– Significant associations between higher levels of PA (i.e., total lifetime, recreational, vigorous PA, and past year) and better cognitive function in later life
Nishiguchi S Yamada M Tanigawa T Sekiyama K Kawagoe T Suzuki M, et al.
– Community-dwelling older adults (N = 48) were randomized into an exercise group (n = 24) and a control group (n = 24).
– Exercise group received a weekly dual task-based multimodal exercise class in combination with pedometer-based daily walking exercise during the 12-wk intervention phase
– Control group did not receive any intervention and were instructed to spend their time as usual during the intervention phase
– The program improved the efficiency of brain activation which is associated with improvements in memory and executive function
– We tested the hypothesis that the nervous system, and the cortex in particular, is a critical determinant of muscle strength/weakness and that a high level of corticospinal inhibition is an important neurophysiological factor regulating force generation.
– Group 1: 4 wks of wrist-hand immobilization to induce weakness
– Group 2: 4 wks of immobilization, but they also performed mental imagery of strong muscle contractions 5 days/wk.
– Group 3: control group
– Mental imagery has been shown to activate several cortical areas that are involved with actual motor behaviors
– Before, immediately after, and 1 wk following immobilization, we measured wrist flexor strength, voluntary activation (VA), and the cortical silent period (SP)
(1) Immobilization decreased strength 45.1 ± 5.0%, impaired VA 23.2 ± 5.8%, and prolonged the SP 13.5 ± 2.6%
(2) Mental imagery training, however, reduced loss of strength and VA by ∼50% (23.8 ± 5.6% and 12.9 ± 3.2% reductions, respectively) and eliminated prolongation of the SP (4.8 ± 2.8% reduction)
(3) Significant associations were observed between the changes in muscle strength and VA and SP
(1) These findings suggest neurological mechanisms, most likely at the cortical level, contribute significantly to disuse-induced weakness
(2) Regular activation of the cortical regions via imagery attenuates weakness and VA by maintaining normal levels of inhibition