Swim drafting for Triathlons

Do you find it frustrating and annoying when other swimmers keep touching your feet in races? As annoying as it may be, the reality is this person is using you to gain significant advantage. So, here’s all the more reason why you should be one of those annoying feet touchers too. 


In race environments ‘drafting’ is a means of reducing drag and environmental resistance by staying behind or close by leading athletes. Drafting means the athlete can travel at higher speeds at a lesser metabolic cost, giving a significant race advantage. Drafting usually has most benefit during cycling, however in the sport of triathlon this stands as an illegal tactic. Although penalties apply for drafting during the cycle leg of triathlon this does not mean that drafting cannot be used in other disciplines within the sport. 

 

 

Similarly to that of cycling, drafting during swimming has significant benefits and is completely legal in the sport of triathlon. Drafting is very well executed among elite and competitive age group triathletes, but even still, if you’re pushing to race a PB or looking for a way to conserve energy for a long race you are making it harder for yourself by not drafting in the water. 


Drafting during swimming is done so by swimming close by or behind another swimmer or group of swimmers. For athletes new to the sport this can seem quite daunting as you may often feel more comfortable with more space around you, but as previously said, this comes at a higher energy expenditure. Drafting works by reducing hydrodynamic drag, which is the drag and/or resistance created by water. As we swim we create a low water pressure area behind us. Therefore, swimming in this low pressure area (that of behind a lead swimmer) helps to facilitate our movement through the water (Delextrat, et al., 2018). This same study also found significant benefits with passive drag, which relates to having a towing like effect from the lead swimmer of 10-26%. Additionally reductions in oxygen uptake, heart rate and levels of blood lactate were also noted. 


Even more reason to use swim drafting to your advantage in triathlon is that the benefits don’t just stop once you exit the water. Results from (Delextrat, et al., 2018) suggest that the reductions in metabolic cost by swim drafting may then bring about significantly higher cycling efficiency.

 

 

 

So, now that we know why we should be drafting in the water, how exactly do we do it? A study completed by (CHATARD & WILSON, 2003) found that the most optimal drafting distance was at 0cm to 50cm behind the lead swimming, also finding an 11-38% reduction in metabolic of the draftee. When swimming alongside another swimming the most optimal distance was 50cm–100cm when the head is at hip level. This position however found a lesser effect with passive drag.


So if you’ve got a foot fetish maybe triathlon is your calling. If instead you’re not such as fan of feet then put your worries aside on race day as it could help you in your next race.  


Zac Turner

Physiotherapist

CHATARD, J.-C., & WILSON, B. (2003). Drafting Distance in Swimming. MEDICINE & SCIENCE IN SPORTS & EXERCISE, 1176 - 1181.


Delextrat, A., Tricot, V., Bernard, T., Vercruyssen, F., Hausswirth, C., & Brisswalter, J. (2018). Drafting during Swimming Improves Efficiency during Subsequent Cycling. HAL, 1612 - 1619.