Chris McNeil, University of Western Ontario

Motor unit number estimates in the tibialis anterior muscle of young, old, and very old men.

According to Mr. McNeil, age-related loss of muscle mass and strength have a profound impact on the ability of older Canadians to successfully carry out the activities of daily living. However, according to him, further investigation is necessary into what changes to the nerve and muscle might precipitate the loss of muscle mass, strength and functional abilities.

Mr. McNeil's research project is a portion of his doctoral dissertation. He is investigating the function of the muscles located on the front of the leg that allow people to lift their toes/foot away from the ground (dorsiflexors) in young (18-35 years) , old (60-69 years), and very old (80 years and above) men.

Volunteers for his research made a single visit to a neuromuscular physiology research laboratory. During the visit, Mr. McNeil assessed lower limb muscle strength with a strain gauge and estimated the number of nerve endings interacting with the muscle (called motor units or MUs) with a small needle electrode inserted into the muscle tissue.

Despite a progressive loss of MUs, muscle mass and strength are maintained in the dorsiflexors (muscles controlling foot drop) until some time between the mid sixties and early eighties. This would indicate that if MU loss could be slowed to any extent, one could postpone the loss of muscle mass and strength in the very old.

Mr. McNeil is currently a PhD candidate in Kinesiology at the University of Western Ontario under the supervision of Dr. Charles Rice. At the completion of his PhD, he intends to obtain a post-doctoral research fellowship and ultimately a University faculty position.