REF-165 · Taylor, Almquist et al., 2021 · International Journal of Sports Physiology and Performance, · Paper · PubMed
The Inclusion of Sprints in Low-Intensity Sessions During the Transition Period of Elite Cyclists Improves Endurance Performance 6 Weeks Into the Subsequent Preparatory Period
Participants
n = 11: Elite male cyclists
SPR group: n = 5
Control group (CON): n = 6 (LIT only)
Context: 3-week transition period post-season; 64% load reduction
Protocol
Transition period: 3 weeks, 64% load reduction from competition period
CON: Low-intensity only (<VT1)
SPR: LIT + 1×/week: 3 sets × 3 × 30s maximal sprints (embedded in LIT session)
Recovery between sprints: ~4 min
Recovery between sets: ~20 min
Additional sprint time: ~4.5 min/week
Testing: Pre-transition, post-transition + 6 weeks standard prep
Tests: 20-min all-out, VO2max, GE, power at 4 mmol [BLa]
Key Findings
| Parameter | SPR (n=5) | CON (n=6) | Difference |
|---|---|---|---|
| 20-min all-out power | +7.3% | –1.3% | SPR advantage |
| Mean VO2 on 20-min test | +7.0% | +0.7% | SPR advantage |
| VO2max | No change | No change | NS |
| Gross efficiency | No change | No change | NS |
| Power at 4 mmol/L | No change | No change | NS |
Mechanisms
Inference, not tested in this paper (only 20-min power, VO2, VO2max, GE and 4 mmol power were measured):
Sprint = neuromuscular stimulus: 30s maximal sprints recruit Type II, prevent detraining even at minimal volume
Performance VO2 vs VO2max: improvement in mean VO2 during 20-min test (+7%) without VO2max change → sprints may improve the ability to sustain a high %VO2max (durability was not measured)
Minimal effective dose: ~4.5 min sprints/week yielded +7.3% power gain → extremely high ROI
Differential response: VO2max and GE unchanged in both groups → sprints affect utilization not capacity
Practical Application
One sprint session a week — 3 sets × 3 × 30 s maximal, ~4 min between sprints, ~20 min between sets, ~4.5 min of sprinting — inside an otherwise low-intensity 3-week transition with a 64% load cut: 6 weeks into the next preparation, 20-min power was +7.3% vs −1.3% for LIT-only and mean VO2 during the 20-min test +7.0% vs +0.7%, in n=11 elite male cyclists (5 vs 6); VO2max, gross efficiency and 4 mmol power changed in neither group.
The lesson is the minimum dose: a few minutes of maximal sprinting keeps neuromuscular recruitment alive through a low-volume period at almost no fatigue cost — so a recovery week, an off-season or a forced light week can carry one sprint set inside an easy ride.
Embed the sprints in the easy session rather than counting them as an interval day; full recovery between efforts is what makes them cheap.
The effect was measured 6 weeks later — it protects the next block's starting point; it is not an in-week performance gain.
n=11 in two unequal groups: the size of the effect is uncertain, its direction is consistent with REF-166.
Limitations
5 vs 6 elite men, not randomised; one transition period.
Source re-verified 2026-09-27 against the abstract: n, groups (5 vs 6), 64% load cut, 3×3×30 s, +7.3% vs −1.3% 20-min power, +7.0% vs +0.7% VO2, no change in VO2max, GE or 4 mmol power.
How this entry was checked and changed
Content correction 2026-09-27
Cross-reference descriptions checked against the cited entries' current content; wrong years, wrong entries and claims the cited entry does not make were corrected.
Resync 2026-09-28: Unlabelled mechanisms, a unilateral-RFD line pasted from REF-148, 'durability' stated as fact, Sport 'sprint' -> mechanisms labelled inference, pasted line removed, durability hedged, Sport = cycling.