Habitual rearfoot (n=19) and forefoot (n=18) runners on a treadmill at 3.0, 3.5 and 4.0 m/s: with their own pattern the groups did not differ in oxygen cost or carbohydrate use; switching to forefoot raised both in rearfoot runners at 3.0 and 3.5 m/s, switching to rearfoot changed nothing in forefoot runners, and at 4.0 m/s the forefoot pattern cost more oxygen with no difference in carbohydrate share
Habitual rearfoot (RF) and forefoot (FF) runners ran with both patterns on a treadmill at three speeds; steady-state oxygen uptake (ml·kg⁻¹·min⁻¹) and carbohydrate share of energy expenditure (%CHO) were measured by indirect calorimetry.
Participants
n=19 habitual RF and n=18 habitual FF runners; sex and level not given in the abstract.
Protocol
RF and FF patterns at 3.0, 3.5 and 4.0 m/s; steady-state VO2 and %CHO; mixed-model ANOVA (α = 0.05).
Key Results
With the habitual pattern, VO2 and %CHO did not differ between RF and FF runners.
RF group: the RF pattern gave lower VO2 and %CHO than the FF pattern at 3.0 and 3.5 m/s (P < 0.05).
FF group: no difference between patterns at 3.0 and 3.5 m/s (P > 0.05).
4.0 m/s: a footstrike main effect, VO2 greater with the FF than the RF pattern (P < 0.05); %CHO not different (P > 0.05).
Authors' conclusion: the FF pattern is not more economical than the RF pattern.
Practical Application
Switching a heel striker to the forefoot cost oxygen and carbohydrate at 3.0 and 3.5 m/s, and at 4.0 m/s the forefoot pattern used more oxygen (main effect across both groups); there is no economy reason to change pattern.
Correcting a blog: switching did not "always" reduce economy (forefoot runners moving to rearfoot showed no change at 3.0 and 3.5 m/s), and forefoot did not need more carbohydrate at the fastest speed (%CHO not different at 4.0 m/s; the extra %CHO appeared only in rearfoot runners at 3.0 and 3.5 m/s).
Inference: the result is acute; whether a runner adapts after weeks of retraining was not tested.
Limitations
Acute, single-session treadmill test; no retraining period.
Sex, training level and order of conditions not stated in the abstract.
Three speeds up to 4.0 m/s; no fatigue or race conditions.
How this entry was checked and changed
Why this level
lab within-subject comparison, both habitual groups; order and randomisation not stated