Exercise Your Nerves
A team of neurologists from UCLA and duPont Hospital for Children in Delaware found that voluntary exercise improves regeneration of neurons, both for those who work out, and for those recuperating after injury. The abstract in PNAS1 states:
Recent advances in understanding the role of neurotrophins on activity-dependent plasticity have provided insight into how behavior can affect specific aspects of neuronal biology. We present evidence that voluntary exercise can prime adult dorsal root ganglion neurons for increased axonal regeneration through a neurotrophin-dependent mechanism. Dorsal root ganglion neurons showed an increase in neurite outgrowth when cultured from animals that had undergone 3 or 7 days of exercise compared with sedentary animals. Neurite length over 18-22 h in culture correlated directly with the distance that animals ran. The exercise-conditioned animals also showed enhanced regrowth of axons after an in vivo nerve crush injury. Sensory ganglia from the 3- and 7-day-exercised animals contained higher brain-derived neurotrophic factor, neurotrophin 3, synapsin I, and GAP43 mRNA levels than those from sedentary animals. Consistent with the rise in brain-derived neurotrophic factor and neurotrophin 3 during exercise, the increased growth potential of the exercise-conditioned animals required activation of the neurotrophin signaling in vivo during the exercise period but did not require new mRNA synthesis in culture.
1Molteni et al., “Voluntary exercise increases axonal regeneration from sensory neurons,” Proceedings of the National Academy of Sciences USA, 10.1073/pnas.0401443101.
Couch potatoing can’t be good for you. Use it and improve it. The discovery that neurons can be regenerated should be good news for those who have suffered injury. Physical therapy may be painful, but it offers hope. Grin and bear it for as long as it takes. Hopefully you’ll be grinning more eventually.