What is the combined effect of physical and mental training?

Phys­i­cal exer­cise and men­tal exer­cise are both ben­e­fi­cial for the brain. Each can improve brain func­tions and decrease risks of cog­ni­tive decline over time. This rais­es the ques­tion of their com­par­a­tive and com­bined effects: Is one bet­ter than the oth­er? Are their ben­e­fits addi­tive (1 + 1 =2) or per­haps even syn­er­gis­tic (1 + 1 =3)?

A recent study sug­gests that the ben­e­fits of each are sig­nif­i­cant and rough­ly equiv­a­lent but nei­ther clear­ly addi­tive not syn­er­gis­tic (mean­ing, that aer­o­bic exer­cise did­n’t make men­tal exer­cise more effec­tive, or vice ver­sa). The study involved 126 old­er adults (mean age of 73.4) with cog­ni­tive com­plaints, that is who felt their mem­o­ry and think­ing skills had declined in the recent past. Par­tic­i­pants were divid­ed onto 4 groups:

As you can see all groups par­tic­i­pat­ed in a men­tal activ­i­ty (1 hour three times a week) and a phys­i­cal activ­i­ty (1 hour three times a week). What dif­fered between them was the type of activ­i­ty per­formed: Watch­ing edu­ca­tion­al DVD was a con­trol group for brain train­ing, that is it was not expect­ed to bring ben­e­fits (or much less). In the same way, stretch­ing and ton­ing was a con­trol for aer­o­bic exercise.

A glob­al cog­ni­tive score was obtained before and after the inter­ven­tion for all par­tic­i­pants, using tests of ver­bal learn­ing and mem­o­ry, ver­bal flu­en­cy, pro­cess­ing speed, exec­u­tive and visu­ospa­tial func­tions and men­tal flex­i­bil­i­ty. The four groups had sim­i­lar scores to start with.

Results showed that all 4 groups glob­al cog­ni­tive func­tion­ing improved after the 12 weeks inter­ven­tion. The com­par­isons between groups 1 and 3 and between groups 2 and 4 showed that both men­tal exer­cise and phys­i­cal exer­cise brought sig­nif­i­cant and rough­ly equiv­a­lent cog­ni­tive benefits.

Sur­pris­ing­ly the com­par­isons between groups 1 and 2 and between groups 3 and 4 (actu­al inter­ven­tions ver­sus con­trol groups) showed that the con­trol activ­i­ties (watch­ing DVD and stretch­ing and ton­ing) trig­gered sim­i­lar ben­e­fits as the inter­ven­tion activ­i­ties (brain train­ing and aer­o­bic). This is not what pre­vi­ous stud­ies have shown: often, brain train­ing or aer­o­bic train­ing bring larg­er ben­e­fits com­pared to mere­ly watch­ing edu­ca­tion­al DVD or stretch­ing and ton­ing. Fur­ther analy­sis on a small sub­group of par­tic­i­pants who had the most mem­o­ry dif­fi­cul­ties showed the usu­al extra ben­e­fit of brain train­ing over edu­ca­tion­al videos.

The authors offer two pos­si­ble expla­na­tions for the results. One is that all the par­tic­i­pants got bet­ter at the cog­ni­tive tests because of a prac­tice effect (remem­ber that they were test­ed before and after the study). Anoth­er expla­na­tion is that for this pop­u­la­tion, that is for old­er adults with mem­o­ry com­plaints, it is not so much the type of activ­i­ty that mat­ters but the mere fact of being active.

A few oth­er stud­ies have also tried to com­pare the ben­e­fits of phys­i­cal and men­tal activity.

A 2006 study con­duct­ed with 375 healthy old­er adults between the ages of 75 and 93 com­pared the effects of men­tal, phys­i­cal and com­bined train­ing. The brain train­ing was done using paper and pen­cil tasks. The phys­i­cal train­ing tar­get­ed bal­ance, flex­i­bil­i­ty and motor coor­di­na­tion. Results showed cog­ni­tive gains only fol­low­ing men­tal and com­bined training.

A small­er 2013 study with 122 healthy adults over 80 com­pared 4 groups: brain train­ing (using Cog­niFit com­put­er­ized exer­cis­es 3 times a week for 16 weeks), phys­i­cal train­ing (aer­o­bic exer­cise 3 times a week for 16 weeks), com­bined train­ing, and con­trol (book read­ing at home and 1 hour dis­cus­sions once a week). Cog­ni­tive gains were observed only fol­low­ing men­tal and com­bined train­ing. The author con­cludes that either the phys­i­cal train­ing inter­ven­tion was not long enough or too mild to yield ben­e­fits or that cog­ni­tive train­ing is the main agent for cog­ni­tive changes.

In con­clu­sion, it is too ear­ly to tell how to best com­bine brain train­ing and phys­i­cal train­ing, but the bulk of the research so far strong­ly sug­gests that they both have mea­sur­able pos­i­tive effects on cog­ni­tion and brain health. Aer­o­bic phys­i­cal exer­cise can improve atten­tion and exec­u­tive func­tions as well as reverse brain vol­ume loss. It usu­al­ly takes 6 months or so to see such ben­e­fits. Brain train­ing can bring steady and sus­tained cog­ni­tive gains after 10 to 15 hours of train­ing, although the gains do not gen­er­al­ly trans­fer to many untrained tasks. And let’s remem­ber that pop­u­la­tion stud­ies have also repeat­ed­ly shown that peo­ple who par­tic­i­pate in men­tal­ly stim­u­lat­ing leisure activ­i­ties through­out their life have health­i­er brains, high­er cog­ni­tive func­tion­ing and low­er risks of demen­tia over the long run.

Sim­ply put, the more we exer­cise our bod­ies and our minds, the better.

Ref­er­ences:

— This arti­cle was writ­ten by Pas­cale Mich­e­lon, PhD. Dr. Mich­e­lon was a Research Sci­en­tist at Wash­ing­ton Uni­ver­sity in Saint Louis, where she is now an Adjunct Fac­ulty. She teach­es mem­ory work­shops in the St Louis area, and con­tributes to SharpBrains.com as the Research Man­ager for The Sharp­Brains Guide to Brain Fit­ness.

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