Systematic review of 39 studies: most found running performance worse after cycling than in a control run, but the physiological and biomechanical explanations conflict, and whether changing cycling cadence or intensity helps the run is unclear
Evidence base
Search of Medline, CINAHL, SportDiscus and Scopus up to 14 December 2021; 7495 records screened, 65 full texts, 39 studies included; quality assessed with the Appraisal tool for Cross-sectional Studies; most studies rated high to very high quality.
Key Findings
The majority of studies observed detrimental effects on performance when running after cycling compared with a control run.
Biomechanical and physiological implications were unclear, with conflicting evidence attributed to varied experimental designs; the authors state it is not possible to say that prior cycling affects subsequent running from a physiological point of view, with unclear biomechanical responses.
Manipulating cycling cadence or intensity has been tested, but evidence on biomechanical, physiological and performance outcomes is conflicting; it is unclear whether either manipulation improves the subsequent run.
Methods used to simulate the cycle-to-run transition varied widely between studies, which is why findings conflict.
Practical Application
Across 39 studies, running performance was mostly worse after cycling than in a stand-alone run, while the physiological and biomechanical reasons remain unresolved and no cadence or intensity manipulation reliably protects the run — treat the run off the bike as its own demand to rehearse in training rather than expecting a pedalling tweak to remove it.
Do not promise a cadence or intensity "fix" for the brick effect; the evidence for any such strategy is conflicting.
Inference, not tested: the earlier wording "reliably degrades running economy and kinematics" overstated the review; the consistent finding is a performance decrement, not an economy decrement.
Limitations
Heterogeneous protocols/populations; mechanism (physiological vs biomechanical vs perceptual) unresolved; no pooled effect size.
Cross-sectional/acute designs dominate; no training-intervention evidence on brick sessions is summarised in the abstract.
How this entry was checked and changed
Why this level
regraded 2026-09-27 from A: systematic review without meta-analysis of heterogeneous, mostly cross-sectional/acute studies with conflicting findings
Content correction 2026-09-27
Title and findings said prior cycling "reliably degrades subsequent running economy and kinematics" -> abstract: most studies found worse running PERFORMANCE after cycling; physiological (economy) and biomechanical effects were unclear and conflicting.
"Cadence/intensity tweaks showed no reliable protective effect" -> abstract: evidence is conflicting/unclear, not a demonstrated null.
Added the evidence base (7495 screened, 65 full texts, 39 included, mostly high quality). Level regraded A -> A- (SR without meta-analysis of heterogeneous studies).