Recent research from Taiwan indicates that engaging in thirty minutes of aerobic exercise can temporarily enhance cognitive function for individuals diagnosed with ADHD.

Under the guidance of neuroscientist Hsiao-I Kuo from National Taiwan University, the study revealed that cardiovascular exercises like brisk walking, jogging, swimming, dancing, or cycling significantly increased inhibition within the motor cortex for those with ADHD. In contrast, individuals without the disorder experienced the opposite effect.

We already know that healthy individuals without ADHD see improvements in their cortex, the area associated with advanced cognitive functions, following aerobic workouts, which also help reduce inhibiting processes affecting neural activity.

A comparable response is noted when non-ADHD individuals consume methylphenidate, a prevalent medication for ADHD that boosts the levels of neurotransmitters like dopamine and norepinephrine.

Conversely, when individuals with ADHD take the stimulant methylphenidate (known by brand names such as Ritalin), there is an increase in intracortical inhibition. This effect may clarify some of its ‘focusing’ benefits, as other studies indicate that ADHD patients typically exhibit much lower intracortical inhibition compared to the general population.

This led the researchers to explore whether aerobic exercise might yield different effects for individuals with ADHD. If it could ‘normalize’ their intracortical inhibition similarly to methylphenidate, could it also enhance cognitive performance?

The study involved 26 unmedicated participants with ADHD, around 23 years old and in otherwise good health, alongside 26 non-ADHD individuals.

During two distinct exercise sessions, each participant used a stationary bike for 30 minutes, commencing with a 5-minute warm-up, followed by a 20-minute workout, and concluding with a 5-minute cool-down.

They also had two ‘control’ sessions, during which participants remained seated on the exercise bike while watching a nature documentary for 30 minutes.

Before and after one of the exercise or control sessions, the research team assessed participants’ performance on cognitive tasks, including one that measured their capacity to stop an activity on command (indicative of inhibitory control) and another focusing on motor learning, akin to ‘muscle memory.’

In the two remaining sessions, TMS (transcranial magnetic stimulation) was employed to evaluate short-interval intracortical inhibition (SICI) and facilitation (ICF).

TMS enables researchers to analyze the signal strength between the motor cortex and various muscles, reflecting neuronal excitability and the modulation of channels that maintain neural network stability.

The results showed that aerobic exercise enhanced SICI in participants with ADHD, who also performed better on both inhibitory control and motor learning tasks after exercising.

Non-ADHD participants experienced improved motor learning after exercising, yet their SICI decreased, with no significant effects on their inhibitory control.

“A single 30-minute session of aerobic activity temporarily boosts cortical inhibition in adults with ADHD, primarily influenced by the GABAergic system,” wrote Kuo and her colleagues. “This may lead to enhancements in inhibitory control and motor learning for individuals with ADHD.”

While the study does not determine if these results are causally linked, they certainly open new avenues for further investigation.

Kuo and her team suggest that short bursts of aerobic exercise could offer cognitive benefits to some ADHD patients in the short term. However, it is unclear if this approach could serve as a standalone treatment or how long the effects might persist.

The research findings are published in Psychiatry Research.