Exercise-Induced Changes in Brain-Derived Neurotrophic Factor in Neurodegenerative Diseases: A Bayesian Network Meta-Analysis.

In 30 seconds

This Bayesian network meta-analysis compared exercise modalities for changing brain-derived neurotrophic factor (BDNF) levels in people with neurodegenerative diseases. It included 42 randomized controlled trials involving 1482 patients. Stretching and high-intensity interval training ranked highest for potential BDNF enhancement (SUCRA = 78.92 and SUCRA = 69.73, respectively), but neither was statistically significantly superior to blank control. Meta-regression found a positive association between intervention period and the effect of combined training (P < 0.01).

Key findings

• Stretching training ranked highest for BDNF enhancement (SUCRA = 78.92), but was not statistically significantly superior to blank control.
• High-intensity interval training ranked second (SUCRA = 69.73), without statistically significant superiority over blank control.
• Combined training’s effect was significantly and positively correlated with intervention period (P < 0.01).
• Aerobic and resistance training had lower rankings for BDNF enhancement (SUCRA = 35.17 and SUCRA = 12.98, respectively).

Why it matters

BDNF is the outcome assessed in this synthesis of exercise interventions for neurodegenerative diseases. The rankings suggest that exercise modalities may differ in their potential to affect BDNF, while the lack of significant superiority over control tempers interpretation. The association between longer intervention periods and combined-training effects also highlights duration as a possible factor in evaluating exercise-related BDNF changes.

What to keep in mind

The reported rankings do not establish statistically significant superiority of stretching or high-intensity interval training over blank control; the findings concern BDNF levels.