Effects of Exercise Vary Based on Age
Antioxidants play an important role in defending cell membranes and
other structures from damage. Studies have found an association between a key regulator of antioxidant signaling, nuclear erythroid-2 like factor-2 (Nrf2), and exercise. According to
2016 research, the relationship between Nrf2 and exercise may be disrupted with age.
The goal of the study, published in Free Radical Biology and Medicine (2016; 96, 130–38), was twofold. First, the researchers wanted to determine whether a high-intensity 30-minute bout of cycling would result in an accumulation of Nrf2. They also wanted to know if this response would be different in older adults.
They recruited 20 men; half were aged 18–30, while the rest were 55 and older. Each participant cycled at 70% of VO2max for 30 minutes. Blood samples were collected at six intervals up until 24 hours postexercise.
The intervention elicited increases in Nrf2 in both the younger and older men. But nuclear import, which allows the factor to reach antioxidant gene targets, was impaired in the older group.
“Additionally we have shown repressed gene expression of downstream antioxidant targets of Nrf2 in older adults,” the authors stated. “Together these translational data demonstrate for the first time the attenuation of Nrf2 activity in response to exercise in older adults.”
It should be noted that this was a small study and featured only one intervention.