The influence of high intensity exercise and the Val66Met polymorphism on circulating BDNF and locomotor learning

Abstract

Brain-derived neurotrophic factor (BDNF) has been directly related to exercise-enhanced motor performance in the neurologically injured animal model; however literature concerning the role of BDNF in the enhancement of motor learning in the human population is limited. Previous studies in healthy subjects have examined the relationship between intensity of an acute bout of exercise, increases in peripheral BDNF and motor learning of a simple isometric upper extremity task. The current study examined the role of high intensity exercise on upregulation of peripheral BDNF levels as well as the role of high intensity exercise in mediation of motor skill performance and retention of a novel locomotor task in neurologically intact adults. In addition, the impact of a single nucleotide polymorphism in the BDNF gene (Val66Met) in moderating the relationship between exercise and motor learning was explored. It was hypothesized that participation in high intensity exercise prior to practicing a novel walking task (split-belt treadmill walking) would elicit increases in peripheral BDNF as well as promote an increased rate and magnitude of within session learning and retention on a second day of exposure to the walking task. Within session learning and retention would be moderated by the presence or absence of Val66Met polymorphism. Fifty-four neurologically intact participants participated in two sessions of split-belt treadmill walking. Step length and limb phase were measured to assess learning of spatial and temporal parameters of walking. Serum BDNF was collected prior to and immediately following either high intensity exercise or 5 minutes of quiet rest. The results demonstrated that high intensity exercise provides limited additional benefit to learning of a novel locomotor pattern in neurologically intact adults, despite increases in circulating BDNF. In addition, presence of a single nucleotide polymorphism on the BDNF gene did not moderate the magnitude of serum BDNF increases with high intensity exercise, nor did it moderate the relationship between high intensity exercise and locomotor learning.

Effectiveness of High‐Intensity Interval Training for Fitness and Mobility Post Stroke: A Systematic Review

“…HIIT also improved walking endurance and balance, although MICE yielded similar improvements . Several potential mechanisms for improved mobility have been proposed in the literature including increased corticospinal excitability and neurotrophin expression, which enhance motor learning . Among individuals with stroke, aerobic exercise may also promote neuroplasticity and neuroprotection .…”

A single exercise bout and locomotor learning after stroke: physiological, behavioural, and computational outcomes

“…This finding agrees with recent work from our lab that found that high intensity exercise also did not promote locomotor learning in neurologically intact adults (Helm et al . ). Moreover, these findings, in both those with stroke and neurologically intact adults, differ from previous studies of the effect of exercise on upper extremity skill learning.…”

“…; Helm et al . ). Briefly, on session 1, we collected blood samples from all subjects to quantify changes in lactate and BDNF concentrations in response to exercise priming.…”

“…Therefore, we collected serum samples from all subjects. For both blood collection and analysis, we used the same experimental procedures as in our previous work (Charalambous et al 2018;Helm et al 2017). Briefly, on session 1, we collected blood samples from all subjects to quantify changes in lactate and BDNF concentrations in response to exercise priming.…”

Acute cardiovascular exercise does not enhance locomotor learning in people with stroke

“…The potential benefits of this type of exercise on other, more complex motor tasks, involving multi‐joint movements of lower limbs, such as those required for locomotion, are less well established (Helm et al . ). Furthermore, most previous studies demonstrating that acute exercise can improve motor memory and skill learning have involved young, healthy individuals.…”