Physical exercise as ADHD treatment: Necessary but not sufficient

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Can exer­cise reduce behav­ior prob­lems and enhance cog­ni­tion in chil­dren with ADHD?

Results from mul­ti­ple stud­ies indi­cate that exer­cise mit­i­gates aging-relat­ed declines in cog­ni­tive func­tion­ing and that it may enhance cog­ni­tive func­tion­ing in old­er adults. Exer­cise has also been shown to be an effec­tive treat­ment for mild to mod­er­ate depression.

Although research on the effects of exer­cise on chil­dren’s cog­ni­tive func­tion­ing is lim­it­ed, a recent­ly pub­lished meta-analy­sis of 8 stud­ies exam­in­ing the effects of exer­cise on chil­dren’s cog­ni­tive per­for­mance con­clud­ed that exer­cise is asso­ci­at­ed with improved cog­ni­tion, aca­d­e­m­ic achieve­ment, behav­ior, and psy­choso­cial func­tion­ing in chil­dren. How­ev­er, the research sup­port­ing this con­clu­sion is based is lim­it­ed and addi­tion­al stud­ies are needed.

What about the impact of phys­i­cal exer­cise on chil­dren with ADHD? Many par­ents whose child has ADHD report that phys­i­cal activ­i­ty is help­ful, so one might expect that this issue has been care­ful­ly stud­ied. How­ev­er, although there have been lit­er­al­ly hun­dreds of stud­ies of med­ica­tion treat­ment for ADHD, almost no research on exer­cise as an ADHD treat­ment has been con­duct­ed. Results from one small study [Exer­cise impact on sus­tained atten­tion of ADHD chil­dren, methylphenidate effects] report­ed sig­nif­i­cant improve­ments on a com­put­er­ized atten­tion test fol­low­ing phys­i­cal activ­i­ty. In a sec­ond study, chil­dren with ADHD and nor­mal con­trols showed improved read­ing and math per­for­mance, and enhanced atten­tion, fol­low­ing a 20-minute exer­cise ses­sion [Exer­cise Improves Behav­ioral, Neu­rocog­ni­tive, and Scholas­tic Per­for­mance in Chil­dren with Atten­tion-Deficit/Hy­per­ac­tiv­i­ty Dis­or­der].

Although these results sug­gest that exer­cise may help chil­dren with ADHD, the clin­i­cal util­i­ty of this work is lim­it­ed by the brief exer­cise dura­tion, i.e., exam­in­ing impact after a sin­gle exer­cise ses­sion, and the absence of any sus­tained fol­low-up. Sev­er­al years ago, how­ev­er, results from a longer tri­al of phys­i­cal activ­i­ty in chil­dren with ADHD were pub­lished [A phys­i­cal activ­i­ty pro­gram improves behav­ior and cog­ni­tive func­tions in chil­dren with ADHD: An explorato­ry study]; these results speak more direct­ly to the promise of exer­cise as a treat­ment for ADHD.

The study was con­duct­ed in France. Par­tic­i­pants were 21 7 to 12-year old chil­dren (19 males) with ADHD; all chil­dren were diag­nosed with the com­bined or hyper­ac­tive-impul­sive sub­type. Chil­dren assigned to the exer­cise treat­ment group were from a sin­gle school; con­trol chil­dren were recruit­ed from dif­fer­ent schools in oth­er areas. Thus, in addi­tion to the small sam­ple size, the study did not use ran­dom assign­ment; this is a sig­nif­i­cant limitation.

Chil­dren in the treat­ment group com­plet­ed a 10-week phys­i­cal activ­i­ty pro­gram at their school. The pro­gram was held 3 days/week for 45 min­utes and includ­ed aer­o­bic, mus­cu­lar, and motor skills exer­cis­es. The objec­tive was to main­tain mod­er­ate to vig­or­ous phys­i­cal activ­i­ty dur­ing each ses­sion. Con­trol chil­dren par­tic­i­pat­ed in what­ev­er phys­i­cal activ­i­ty was offered at their school but had no spe­cial pro­gram. All chil­dren who were tak­ing med­ica­tion at base­line con­tin­ued to do so.

Par­ents and teach­ers com­plet­ed behav­ior rat­ings using the Child Behav­ior Check­list before and after the phys­i­cal activ­i­ty pro­gram. Objec­tive assess­ments of atten­tion func­tion­ing and response inhi­bi­tion were obtained at sim­i­lar inter­vals using the Test of Every­day Atten­tion. Rat­ings and atten­tion test­ing were obtained before and after the inter­ven­tion for 18 of the 21 participants.

Results

After con­trol­ling for base­line rat­ings, chil­dren in the exer­cise group had sig­nif­i­cant­ly low­er par­ent rat­ings at post-test for social prob­lems, atten­tion prob­lems, thought prob­lems, and Total Prob­lems. Scores for the ‘with­drawn-depres­sion’ scale were mar­gin­al­ly low­er. How­ev­er, despite the ben­e­fits asso­ci­at­ed with exer­cise, aver­age scores for chil­dren in the exer­cise group remained clin­i­cal­ly ele­vat­ed on most scales. Teacher rat­ings con­sis­tent­ly favored chil­dren in the exer­cise group but were sta­tis­ti­cal­ly sig­nif­i­cant only for the anx­i­ety-depres­sion score and the social prob­lems score.

Results for the Test of Every­day Atten­tion indi­cat­ed that chil­dren in the exer­cise group showed improve­ment in sus­tained audi­to­ry attention.

Sum­ma­ry and Implications

Results from this explorato­ry study pro­vide pre­lim­i­nary evi­dence that exer­cise may reduce behav­ior prob­lems and enhance atten­tion in chil­dren with ADHD. This is evi­dent in the rat­ings pro­vid­ed by par­ents and, to a less­er extent, in teacher rat­ings. There was also some evi­dence of improved atten­tion on an objec­tive test. Even so, how­ev­er, rat­ings for chil­dren in the exer­cise group tend­ed to remain in a clin­i­cal­ly ele­vat­ed range.

While these results are promis­ing, the study is lim­it­ed by the small sam­ple size and absence of ran­dom assign­ment to treat­ment and con­trol groups. In addi­tion, par­ents and teach­ers were not blind to chil­dren’s sta­tus and this may have influ­enced the rat­ings for chil­dren in the exer­cise group.

It is strik­ing that despite the thou­sands of stud­ies that have been con­duct­ed on ADHD, this is the sin­gle tri­al I could find that exam­ines exer­cise as an inter­ven­tion. And, for the rea­sons not­ed above, this is real­ly a very pre­lim­i­nary investigation.

Hope­ful­ly, larg­er and bet­ter con­trolled stud­ies of exer­cise as an ADHD inter­ven­tion will be forth­com­ing short­ly as such work is cer­tain­ly over­due. In the mean­time, a sys­tem­at­ic phys­i­cal activ­i­ty pro­gram should pro­vide impor­tant health ben­e­fits to all chil­dren, and may play a com­ple­men­tary role in reduc­ing the behav­ioral and cog­ni­tive prob­lems asso­ci­at­ed with ADHD.

– Dr. David Rabin­er is a child clin­i­cal psy­chol­o­gist and Direc­tor of Under­grad­u­ate Stud­ies in the Depart­ment of Psy­chol­ogy and Neu­ro­science at Duke Uni­ver­sity. He pub­lishes Atten­tion Research Update, an online newslet­ter that helps par­ents, pro­fes­sion­als, and edu­ca­tors keep up with the lat­est research on ADHD, and teach­es the online course  How to Nav­i­gate Con­ven­tion­al and Com­ple­men­tary ADHD Treat­ments for Healthy Brain Devel­op­ment.

To learn more:

• ADHD Study: Reduc­ing the need for high med­ica­tion dos­es with behav­ior therapy
• Study: Neu­ro­feed­back brain train­ing can com­ple­ment ADHD stim­u­lant medications