dc.contributor.author | Muggeridge, David | |
dc.contributor.author | Sculthorpe, Nicholas | |
dc.contributor.author | Fergal, Grace | |
dc.contributor.author | Willis, Gareth | |
dc.contributor.author | Thornhill, Laurence | |
dc.contributor.author | Weller, Richard | |
dc.contributor.author | James, Philip | |
dc.contributor.author | Easton, Chris | |
dc.date.accessioned | 2017-01-17T16:10:01Z | |
dc.date.available | 2017-01-17T16:10:01Z | |
dc.date.issued | 2015-08-01 | |
dc.identifier.citation | Muggeridge, D.J, Sculthorpe, N, Grace, F.M, Willis, G, Thornhill, L, Weller, R.B, James, P.E & Easton, C. (2015) 'Acute whole body UVA irradiation combined with nitrate ingestion enhances time trial performance in trained cyclists' Nitric Oxide: Biology and Chemistry, 48 pp.3-9 | en_US |
dc.identifier.issn | 1089-8603 | |
dc.identifier.uri | http://hdl.handle.net/10369/8305 | |
dc.description.abstract | Abstract
Dietary nitrate supplementation has been shown to increase nitric oxide (NO) metabolites, reduce blood pressure (BP) and enhance exercise performance. Acute exposure to ultraviolet (UV)-A light also increases NO bioavailability and reduces BP. We conducted a randomized, counterbalanced placebo-controlled trial to determine the effects of UV-A light alone and in combination with nitrate on the responses to sub-maximal steady-state exercise and time trial (TT) performance. Nine cyclists (VO2max 53.1 ± 4.4 ml/kg/min) completed five performance trials comprising 10 min submaximal steady-state cycling followed by a 16.1 km TT. Following a familiarization the final four trials were preceded, in random order, by either (1) Nitrate gels (NIT) + UV-A, (2) Placebo (PLA) + UV-A, (3) NIT + Sham light (SHAM) and (4) PLA + SHAM (control). The NIT gels (2 × 60 ml gels, ~8.1 mmol nitrate) or a low-nitrate PLA were ingested 2.5 h prior to the trial. The light exposure consisted of 20 J/cm2 whole body irradiation with either UV-A or SHAM light. Plasma nitrite was measured pre- and post-irradiation and VO2 was measured continuously during steady-state exercise. Plasma nitrite was higher for NIT + SHAM (geometric mean (95% CI), 332 (292–377) nM; P = 0.029) and NIT + UV-A (456 (312–666) nM; P = 0.014) compared to PLA + SHAM (215 (167–277) nM). Differences between PLA + SHAM and PLA + UV-A (282 (248–356) nM) were small and non-significant. During steady-state exercise VO2 was reduced following NIT + UVA (P = 0.034) and tended to be lower in NIT + SHAM (P = 0.086) but not PLA + UV-A (P = 0.381) compared to PLA + SHAM. Performance in the TT was significantly faster following NIT + UV-A (mean ± SD 1447 ± 41 s P = 0.005; d = 0.47), but not PLA + UV-A (1450 ± 40 s; d = 0.41) or NIT + SHAM (1455 ± 47 s; d = 0.28) compared to PLA + SHAM (1469 ± 52 s). These findings demonstrate that exposure to UV-A light alone does not alter the physiological responses to exercise or improve performance in a laboratory setting. A combination of UV-A and NIT, however, does improve cycling TT performance in this environment, which may be due to a larger increase in NO availability | en_US |
dc.language.iso | en | en_US |
dc.publisher | Elsevier | en_US |
dc.relation.ispartofseries | Nitric Oxide | |
dc.subject | Exercise | en_US |
dc.subject | Nitric Oxide | en_US |
dc.subject | cyclists | en_US |
dc.subject | ingestion | en_US |
dc.subject | time trial performance | en_US |
dc.title | Acute whole body UVA irradiation combined with nitrate ingestion enhances time trial performance in trained cyclists | en_US |
dc.type | Article | en_US |
dc.identifier.doi | http://dx.doi.org/10.1016/j.niox.2014.09.158 | |
dcterms.dateAccepted | 2015-04-01 | |
rioxxterms.funder | Cardiff Metropolitan University | en_US |
rioxxterms.identifier.project | Cardiff Metropolian (Internal) | en_US |
rioxxterms.version | AM | en_US |
rioxxterms.licenseref.uri | http://www.rioxx.net/licenses/all-rights-reserved | en_US |
rioxxterms.licenseref.startdate | 2017-01-17 | |
rioxxterms.funder.project | 37baf166-7129-4cd4-b6a1-507454d1372e | en_US |