Study: Building muscle mass helps delay cognitive decline beyond the value of exercise itself

A new rea­son to build mus­cle: brain health (The Globe and Mail):

… a recent study from researchers at McGill Uni­ver­si­ty, pub­lished in the jour­nal JAMA Net­work Open, offers a new rea­son for con­tin­u­ing to work on build­ing mus­cle: It’s good for your brain, not just your biceps. Greater mus­cle mass, the results sug­gest, helps ward off cog­ni­tive decline in old­er adults beyond what you’d expect based on their exer­cise lev­els alone.

The find­ings are drawn from more than 8,000 old­er adults in the Cana­di­an Lon­gi­tu­di­nal Study on Aging, with an aver­age age of 73. They under­went a series of base­line assess­ments that includ­ed an X‑ray mea­sure­ment of their mus­cle mass, a bat­tery of 10 cog­ni­tive tests and ques­tion­naires about their exer­cise habits and oth­er health char­ac­ter­is­tics. The cog­ni­tive tests were repeat­ed three years later…

Teas­ing out exact­ly how mus­cle helps the brain remains a chal­lenge. There are plen­ty of indi­rect links: Those with more mus­cle are gen­er­al­ly more active, which may help main­tain the flow of oxy­gen-rich blood to the brain, for example.

But Dr. Chevalier’s results sug­gest there may be more direct mech­a­nisms too. One pos­si­bil­i­ty is the role of myokines, a set of hor­mone-like mol­e­cules pro­duced by mus­cle cells that can trav­el to the brain and influ­ence mood, learn­ing and oth­er cog­ni­tive func­tions. Greater mus­cle mass may also help keep blood glu­cose lev­els in check, pro­tect­ing the brain from damage.

The Study:

Asso­ci­a­tion of Low Mus­cle Mass With Cog­ni­tive Func­tion Dur­ing a 3‑Year Fol­low-up Among Adults Aged 65 to 86 Years in the Cana­di­an Lon­gi­tu­di­nal Study on Aging (JAMA Net­work Open). Key Points:

• Ques­tion: Is low mus­cle mass asso­ci­at­ed with declines in dif­fer­ent cog­ni­tive domains over 3 years?
• Find­ings: In cohort study that includ­ed 8279 old­er adults, the pres­ence of low mus­cle mass was sig­nif­i­cant­ly and inde­pen­dent­ly asso­ci­at­ed with faster sub­se­quent exec­u­tive func­tion decline over 3 years.
• Mean­ing: These find­ings sug­gest the poten­tial for clin­i­cal screen­ing of old­er adults to iden­ti­fy those with low mus­cle mass to assist in risk detec­tion of cog­ni­tive impair­ment development.

The Study in Context: