Purpose: The purposes of this study were first to compare the physiological
responses during a triathlon where cycling was performed alternatively wit
h another cyclist (alternate draft triathlon, ADT) or continuously behind h
im (continuous draft triathlon, CDT), and second to study the incidence of
these two drafting modalities in cycling on the subsequent running performa
nce done during a simulated triathlon. Methods: Ten male triathletes of nat
ional level performed a sprint distance triathlon (0.75-km swim, 20-km bike
, 5-km run) on two different sessions, one where the triathlete alternative
ly rode in front or at the back of another cyclist and rotating every 500 m
, the other where the triathlete drafted continuously a professional cyclis
t whose task was to reproduce all split times recorded during the alternate
situation. Oxygen uptake ((V) over dot O-2), expiratory flow ((V) over dot
E), heart rate (HR) were recorded during the entire bike and run sections
and blood lactate concentrations ([La-](b)) were analyzed at the end of eac
h event composing the triathlon. Results: The results showed that expirator
y flow, oxygen uptake. heart rate and blood lactate concentrations were sig
nificantly lower in CDT on the bike compared with drafting in alternation (
148.1 vs. 167.2 L.min(-1), 49.9 vs. 59.8 mL.min(-1).kg(-1), 154.7 vs. 173.1
beats.min(-1), 3.5 vs. 6.3 mmol.L-1, respectively). The results also revea
led that running after biking in CDT (for similar cycling speeds) significa
ntly improved the subsequent running speed compared to ADT (17.87 vs. 17.15
km.h(-1)). Furthermore, (V) over dot E. (V) over dot O-2, HR, and [La-](b)
were significantly higher during CDT run compared with ADT run (175.6 vs.
170.4 L.min(-1), 69.7 vs. 66.8 mL.min(-1).kg(-1), 182.6 vs. 177.3 beats.min
(-1), 9.6 vs. 7.5 mmol.L-1, respectively). Conclusions: These results showe
d that drafting continuously behind a lead cyclist allows triathletes to sa
ve a significant amount of energy during the bike leg of a sprint triathlon
and creates the conditions for an improved running performance compared wi
th a situation where cycling is performed alternating the lead with another
cyclist.