Aerobics do improve neurocognitive performance, but only modestly, say researchers.
Several previous studies on the effects of exercise
on neurocognition have been hampered by methodological
shortcomings and could even be outdated as a result of the recent
publication of several large-scale, randomized, controlled trials
(RCTs), Duke University Medical Center researchers felt. So they set to study the issue afresh.
They conducted a systematic literature review of RCTs
examining the association between aerobic exercise training
on neurocognitive performance between January 1966 and July
2009. Suitable studies were selected for inclusion according
to the following criteria: randomized treatment allocation;
mean age of 18 years; duration of treatment more than a 1 month;
incorporated aerobic exercise components; supervised exercise
training; the presence of a nonaerobic-exercise control group;
and sufficient information to derive effect size data.
Twenty-nine studies met inclusion criteria and were
included in their analyses, representing data from 2049 participants
and 234 effect sizes. They found that individuals randomly assigned to receive
aerobic exercise training demonstrated modest improvements in
attention and processing speed.
So the researchers led by Patrick Smith of the Department of Psychiatry and Behavioral Sciences at the Duke University Medical Center said, "Aerobic exercise training is associated with modest
improvements in attention and processing speed, executive function,
and memory, although the effects of exercise on working memory
are less consistent. Rigorous RCTs are needed with larger samples,
appropriate controls, and longer follow-up periods. "