The effect of 1 week of repeated ischaemic leg preconditioning on simulated Keirin cycling performance: a randomised trial

Abstract

BackgroundCoaches continually seek new ways of doing things and also refine existing techniques to improve sporting performance. Coaches are currently experimenting using ischaemic preconditioning (IPC) over consecutive days in the hope of improving competitive performances.AimsFirst, to quantify the physiological impact of 1 week of IPC on simulated Keirin cycling performance. Second, to investigate if biochemical stress markers are affected over the treatment period.MethodsUsing a randomised, sham-controlled design, 18 active adults undertook seven consecutive days of IPC treatment (4×5 min occlusion/reperfusion) applied to each leg at either 220 mm Hg (treatment, n=9) or 20 mm Hg (sham, n=9). Urinary measures of inflammation, oxidative stress and indirect nitric oxide synthesis were undertaken daily. A simulated Keirin cycling competition (4×30 s Wingate tests) was performed on day 10, with baseline and postintervention cycling VO2max (days 1, 11 and 18) and 30 s Wingate tests (day 2) undertaken for comparison.ResultsThe treatment group had enhanced mean cycling power (3.4%), while neopterin and biopterin in conjunction with total neopterin were significantly lower (p<0.05) and total biopterin significantly greater (p<0.05) during the simulated Keirin. Aerobic fitness measures significantly improved from baseline to postintervention (VO2peak: 12.8% ↑, maximal aerobic power: 18.5% ↑).ConclusionsSeven consecutive days of IPC improved aerobic and anaerobic capacity measures, with modulations in oxidative stress, immune system activation and nitric oxide/catecholamine synthesis.

The effect of ischaemic preconditioning on central and peripheral fatiguing mechanisms in humans following sustained maximal isometric exercise

“…However, sEMG measures are influenced by multiple factors, rendering comparisons between electrical activity within the muscle and neural drive inappropriate (Dimitrova & Dimitrov, 2003;Farina et al, 2010). Alternatively, these increases in sEMG signals might in fact be related to humoral benefits induced by IPC enabling an increase in skeletal muscle performance (Bailey et al, 2012a;Lindsay et al, 2017;Paradis-Deschênes et al, 2016, 2017. As such, prior observations of increased sEMG activity might have been a byproduct of IPC-augmented humoral pathways, rather than a direct neural response.…”

Ischemic Preconditioning Enhances Performance and Erythrocyte Deformability of Responders

“…Following these observations, many studies were conducted to evaluate the effects of IPC on different types of exercise performance [27]. But the results are very heterogeneous, showing beneficial [3,9,10,13,19,20,28,31,38,45,51], detrimental [2,48], and no effects [7, 14-16, 23, 34, 42, 43, 55, 56, 61] of IPC on performance. The different performance outcomes might be due to an inconsistency of influencing variables such as gender [50], and training status of the subjects (highly trained [28] or recreationally active [61]), included number of occlusion and reperfusion cycles [2,3], applied body sites (arm [34] or leg [56]), type of exercise (cycling [19], running [55], swimming [13], or resistance [54]), length of exercise (short/sprint [16], long distance [56], or incremental exercise [20]), and time duration between the end of the IPC manoeuvre and start of physical exercise [40].…”

Pterins as diagnostic markers of exercise-induced stress: a systematic review

“…Studies included a range of cycling intensities from 140 beats/min for one hour 32 to a 4763 km extreme endurance cycling race 33 to a simulated Keirin cycling event. 34 Studies measuring neopterin all observed a significant increase immediately post-exercise, except one. 32 Smith et al 32 measured no change up to 6 h post-cycling at 140 beat/min for one hour suggesting the intensity was not sufficient to induce T-cell release of ␥-IFN.…”

“…In contrast, cycling 230 km, 35 4763 km, 33 to exhaustion 36,37 or repetitively at maximal intensity for 30 s 34 all resulted in significant increases that remained elevated from 60 min 36 to 16 days. 33 Total neopterin also increased immediately post-cycling in response to a continuous exhaustion protocol 36 or repeated maximal bouts of 30 s. 34 When biopterins were measured, cycling at 80% VO 2 max caused a 150% increase in BH 4 and total biopterin 38 while repeated maximal bouts of 30 s 34 only increased biopterin. Taken together, cycling of various intensities causes an increase in several pterins, specifically neopterin, with limited data on biopterins and the longitudinal response.…”