A New Aerodynamic Edge in the Sub 2 Hour Marathon Chase
A new study led by Professor Bert Blocken has put aerodynamic drafting marathon science firmly in the spotlight, suggesting that optimised packs could cut up to 40 seconds from marathon times under favourable conditions. Using advanced Computational Fluid Dynamics simulations backed by wind tunnel tests, the researchers modelled groups of up to 45 runners to understand how air moves in and around a pack. Their findings challenge the long-standing belief that aerodynamics only matter at sprinting or cycling speeds. For elites flirting with the sub 2 hour marathon barrier and a current official world record of 2:00:35, a potential 30–40 second gain is huge. The work indicates that running in a well-structured pack can slash air resistance by as much as 90 percent compared with running solo, redefining how coaches might think about marathon pacing strategy and group formation.
How Wind Resistance Actually Slows Runners Down
At marathon speeds, runners are not cutting through the air like cyclists in a time trial, but wind resistance still quietly taxes their energy. Imagine running on a calm day versus into a mild headwind; even a small breeze forces your body to push air aside with every step. The study shows that this aerodynamic drag matters more than many assumed, especially over 42.2 kilometres. In simple terms, the faster you move, the more the air pushes back, and the cost compounds over time. When a runner tucks into a pack, the leading athletes absorb most of that impact, leaving those behind in a pocket of slightly calmer, lower-pressure air. Surprisingly, the researchers also identified a forward-pushing airflow from runners behind, a phenomenon commonly seen in cycling, meaning the benefits are not just for the people at the back of the group.
Elite Marathon Tactics: Smarter Packs, Smarter Pacers
For elite squads and race organisers, the findings open new possibilities for marathon pacing strategy. The research compared more than 24 pack configurations, varying spacing, alignment and group composition, even including mixed-gender packs. It found that the greatest aerodynamic benefit comes from being positioned within a well-structured formation rather than off to the side or drifting behind at irregular distances. By stacking pacers in carefully designed shapes and rotating who faces the air most often, teams may help their star athlete conserve more energy for a decisive late surge. Race organisers could also design pacer groups with specific aerodynamic goals in mind, much as cycling teams plan lead-out trains. Fine-tuning apparel and body position adds a few more seconds; tight-fitting clothing and streamlined headwear were found to contribute around five to ten seconds of potential gain on top of pack positioning.
Limits of the Data: From Perfect Simulations to Imperfect Roads
Despite the headline-grabbing numbers, there are clear limits to what this research can promise in the real world. The simulations and wind tunnel tests were done under controlled conditions; actual marathons are messy. Weather shifts mid-race, courses twist and rise, and athletes rarely hold textbook-perfect positions for two hours. Even Professor Blocken notes that every race condition cannot be replicated exactly, only modelled to reveal which aerodynamic strategies offer the biggest gains. In crowded fields, runners jostle for space, lose contact with their intended pack, or are forced to surge around others, burning extra energy. Tactical decisions, fuelling, and an individual’s response to pace changes can quickly overshadow any theoretical advantage from drafting. Aerodynamics is one important lever among many, and while it may help shave seconds at the front, it cannot compensate for poor pacing or inadequate preparation.
What Everyday Runners Can Learn About Running in a Pack
For non-elite runners, aerodynamic drafting marathon gains will not be as dramatic, but the principles still matter. Running in a pack can ease perceived effort by sheltering you from wind and giving a steady rhythm to lock into. The key is choosing a group moving at your realistic goal pace; tucking behind a faster pack will simply lead to early fatigue. Good etiquette is crucial: avoid clipping heels, hold a predictable line, and take your turn on the front when you can, especially in small groups. If conditions are breezy, try running a half-step behind and slightly to the side of another runner to benefit without crowding. Above all, treat drafting as a small efficiency bonus, not a magic solution. Smart pacing, fuelling and preparation still drive performance, but using packs thoughtfully can help you finish stronger and more comfortably.