REF-745 · Faulkner SH, Ferguson RA, Gerrett N, Hupperets M, Hodder SG, Havenith G — 2013 · Medicine & Science in Sports & Exercise · Paper
During a 30-min wait after a 15-min warm-up, electrically heated pants kept thigh muscle temperature elevated and raised 30-s sprint peak power by 9.6% versus ordinary tracksuit pants; insulated pants without heating did not
The warm-up's benefit is lost in the gap before the start, and active heating keeps it
Protocol
15-min intermittent warm-up on a cycle ergometer, identical on all three visits.
30-min passive recovery wearing a tracksuit top with CONT (standard tracksuit pants), INS (insulated athletic pants) or HEAT (insulated pants with integrated electric heating elements), in randomised order.
30-s maximal sprint; vastus lateralis temperature at 1, 2 and 3 cm before and after the warm-up and immediately pre-sprint; blood lactate immediately post-sprint.
Key Findings
The warm-up raised muscle temperature by ~2.5 °C at all depths, identically in all conditions.
During the 30-min wait, muscle temperature remained elevated only with heating (HEAT vs INS and CONT, p < 0.001 at all depths); insulation alone did not hold it.
Peak power +9.6% and relative peak power +9.1% in HEAT versus CONT (both p < 0.05); INS was not significantly different from CONT.
Post-sprint lactate rose more after HEAT (6.3 ± 1.8 mmol/L) than INS (4.0) or CONT (4.1): the warmer muscle did more work.
Practical Application
When there is a wait between the end of the warm-up and the start (the trial tested 30 min) — a cyclocross or XCO grid, a track or TT holding area, a cold criterium call-up — keep the working muscles actively warm: electrically heated pants or pads over the thighs, removed at the last minute. In this trial that was worth ~10% of first-sprint peak power, and passive insulation alone did not deliver it (though it is still the sensible floor — REF-269, REF-264).
Not from this paper; the base's own practice: time the warm-up to end as late as the schedule allows and treat the gap as part of the protocol. REF-276 found a short warm-up beat a long one on peak power; it did not test timing, so "finished late" is practice, not its finding.
Cold-weather off-road racing (autumn–winter cyclocross) is the prime case: the start is a 15–30 s all-out sprint into the first corner and it happens after standing still in the wind (REF-740).
Limitations
Outcome is a single 30-s sprint; the effect on a 45–60 min race after the start is not measured — the literature on passive heat maintenance finds a clear peak-power effect and no time-trial effect (REF-269 for the review context).
n = 11 trained men, laboratory conditions (a still, controlled wait, not a windy field); a colder field would widen the gap, a warmer day would narrow it.
Heated garments are a specific product; ordinary insulation did not reproduce the effect here.
How this entry was checked and changed
Content correction 2026-09-27
"A wait of 10–30 min" → the trial tested a 30-min recovery; the shorter end of the range was not tested.
2026-09-29: the practice line credited REF-276 with "a short warm-up finished late beats a long one finished early"; REF-276 compared warm-up length, not timing — relabelled as the base's practice.