My favorite topic to learn about was muscle cramps. For me, this was most surprising. The book cites this as a result of involuntary muscle contractions but it is unclear if it comes from the peripheral nervous system or the central nervous system. For something that is so common-you would think they knew the cause by now! I have always thought that this was a result of dehydration-as I experience leg cramps when I am dehydrated all the time.

But as we have learned, there is not a lot of evidence to link dehydration or electrolyte imbalance to muscle cramps. The book cites that muscle cramps are likely due to changes in the central nervous system. Potential causes of increased motor neuron excitability include high levels of excitatory input to the motor neurons and/or the lack of inhibitory input to the motor neurons. Those promote dysfunction of the muscle spindle and/or the Golgi tendon organ. There are several lines of evidence support the view that exercise can promote dysfunction of muscle sense organs and trigger muscle cramps.

I also enjoyed watching everyone’s presentations (so far). It is always interesting to see where someone takes a topic and what studies they find!