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Genetics play key role in running performance, research shows
Scientists have identified 19 genes linked to athletic improvement, but training and technique remain critical for speed and endurance.
The science of speed
Running is one of the world's most accessible sports, with over 64 million participants in the U.S. alone. Marathon entries nearly doubled from 2021 to 2022, while Parkrun reported 8.5 million registered runners in 2023. Yet what separates elite athletes from casual runners may lie in their DNA.
Researchers at Essex University analyzed 3,000 genes in 45 British adults over an eight-week training program. Participants ran 30 minutes, three times weekly. While the average improvement in VO₂ max-a key measure of aerobic fitness-was 10%, results varied widely. Some saw a 20% boost, others just 5%, and a few showed no progress.
Genotype analysis revealed 19 genes consistently linked to fitness gains. Those with all 19 genes improved the most, while others had only one or two. Among them was the ACTN3 gene, known as the "speed gene," which influences fast-twitch muscle fibers critical for sprinting.
Elite athletes and genetic advantage
Irish middle-distance runner Ciara Mageean, a Commonwealth Games silver medalist and Parkrun world-record holder (15:13 for 5K), credits her success to both genetics and relentless training. "I feel it's impossible to compete at the top level without that genetic component," she said. Yet she admits her talent wasn't immediately obvious. "I grew up playing camogie and wasn't the fastest in sprints."
Mageean's story highlights a key finding: while genetics provide an edge, they don't guarantee success. Over 200 genetic variations influence athletic performance, but training, environment, and mental resilience are equally vital.
Training techniques to improve speed
Steffi Colyer, a biomechanics expert at the University of Bath, explains that running faster requires applying greater force to the ground relative to body weight. "The mechanical demands of sprinting change dramatically as you accelerate," she said. "Contact time with the ground decreases, so you must generate force quickly."
Colyer advises runners to focus on form: landing under the body, minimizing ground contact, and rapidly recovering the leg. Mageean adds practical tips, including hill sprints, tempo runs, and fartlek training (intervals of fast and slow running). "I think 'tap, tap, tap' to remind myself to move my legs quickly," she said.
Beyond speed: the broader benefits of running
While genetics may limit peak performance, running offers universal benefits. Studies show it strengthens the heart, bones, and mental health, and may even extend lifespan. "Slow running can be more beneficial than fast," Mageean noted, reducing injury risk while improving VO₂ max.
Chung, the sports scientist, sums it up: "If you've got the genes and you work hard, you could be unstoppable." But for most, the joy of running lies beyond the clock. As Mageean puts it, "I have so much respect for those who strive to get the best out of themselves, regardless of what they were born with."
