REF-805 · Weyand et al., 2000 · Journal of Applied Physiology, Vol. · Paper · PubMed

Faster top running speeds are achieved with greater ground forces not more rapid leg movements

Blimited evidenceMeasured on recreational to elite athletesWritten before October 2026, being re-checked

Two tests of whether top running speed is set by the force applied to the ground or by how quickly the limbs are repositioned in the air. First, 33 subjects of different sprinting abilities ran at top speed on a level treadmill with a treadmill-mounted force plate (top speeds spanned 1.8-fold, from 6.2 to 11.1 m/s).

The average vertical force during foot contact, relative to body weight, was 1.26 times greater for a runner with a top speed of 11.1 than of 6.2 m/s, while swing time did not vary (P = 0.18).

Second, five subjects ran at top speed declined (-6 degrees) and inclined (+9 degrees): the faster declined top speeds (9.96 ± 0.3 vs 7.10 ± 0.3 m/s) came with 1.3 times greater support forces and similar minimum swing times (+8%).

Participants

Test 1: 33 subjects of different sprinting abilities. Test 2: five subjects. Sex, age and training background are not given in the abstract.

Protocol

Treadmill-mounted force plate; top-speed running on a level treadmill (test 1) and at -6 and +9 degrees (test 2).
Swing time (t(sw)) = time between stance periods of the same foot.
Force relevant for speed = force normal to the ground divided by body weight, averaged over foot-ground contact (F(avge)/W(b)).

Key Results

Top speeds spanned a 1.8-fold range, 6.2 to 11.1 m/s.
F(avge)/W(b) was 1.26 times greater for a runner with a top speed of 11.1 vs 6.2 m/s.
Swing time did not vary with top speed (P = 0.18).
Declined vs inclined top speed: 9.96 ± 0.3 vs 7.10 ± 0.3 m/s (1.4-fold); mass-specific support forces 2.30 ± 0.06 vs 1.76 ± 0.04 F(avge)/W(b) (1.3 times greater); minimum swing times similar (+8%).
Authors' conclusion: faster top speeds come from applying greater support forces to the ground, not from repositioning the limbs more rapidly in the air.

Practical Application

"Is top speed about fast legs or strong legs?" — in 33 runners of different abilities tested on a treadmill force plate, the fastest (11.1 m/s) applied 1.26 times more ground force per body weight than the slowest (6.2 m/s), while the time to swing the leg through did not differ: top speed comes from pushing harder into the ground, not from quicker leg turnover.
Do not coach top speed mainly through faster leg cycling drills; the swing phase did not separate fast from slow runners here.
Inference, not tested here: strength and plyometric work that raises the force a runner can apply in a short contact is a plausible route to top speed; this study measured the determinant, not a training response. The training evidence is REF-764 and REF-804.
Maximal velocity is a vertical-force problem; acceleration is a question of force orientation (REF-806). Not from this paper; the base's own practice: profile which one limits the athlete before choosing methods (REF-553).

Limitations

Treadmill top-speed running; overground sprinting may differ.
Cross-sectional: shows that faster runners apply more force, not that raising force makes a runner faster.
Only vertical (normal) force averaged over contact was used as the speed-relevant force; horizontal force is not reported in the abstract.
Written from the abstract and record metadata only (full text not read).
How this entry was checked and changed
Why this level

cross-sectional, n=33, plus a within-subject test in 5