PurposeThe aim of our study was to analyse the effect of a single-cycle ischaemic preconditioning (IPC) protocol on performance in the 100-m front crawl swimming modality.MethodsOverall, 16 swimmers were recruited: 8 female athletes (12.9 ± 0.88 years) and 8 male athletes (13.1 ± 0.88 years). In a randomized crossover design, all participants performed a 100-m front crawl sprint preceded by an IPC or placebo cycle. In the IPC trial, a pneumatic cuff was attached to the proximal thigh and was inflated at a pressure equivalent to 80% of arterial occlusion and remained inflated for 5 min (ischaemia); in the placebo trial, the cuff remained inflated for the same amount of time, but at low external pressure levels (20 mm Hg). The volunteers started the test 5 min after cuff pressure release (reperfusion).ResultsIt was not possible to verify significant differences within the time (seconds) required to complete the test between the IPC and placebo interventions (75.68 ± 7.2 and 75.75 ± 8.1 s, respectively; <i>p</i> = 0.916).ConclusionsTherefore, we can conclude that the tested IPC protocol does not seem to be sufficient to provide performance improvement in 100-m front crawl in young athletes.