title: Effect of self-administered stretching on NIRS-measured oxygenation dynamics.
abstract: This study determined human skeletal muscle oxygenation dynamics during and after a single bout of self-administered stretching (SAS) of the plantar flexors. Nine healthy recreationally fit men (n = 7; age = 25·7 years) and women (n = 2; age = 23·5 years) performed two protocols: (i) one bout of SAS for 4 min and (ii) one bout of moderate intensity cycling for 4 min. We used near infrared spectroscopy to measure changes in muscle deoxygenated haemoglobin-myoglobin ([HHb]) and blood volume ([Hbtot ]) of gastrocnemius medialis muscle before, during and after stretching. The SAS caused an increase (P<0·05) in [HHb] during stretching between 60 and 240 s relative to baseline, but not at 30 s. No significant difference was found for [Hbtot ] at any time interval during SAS. Furthermore, the increase in local blood flow (suggested by [Hbtot ] changes) was found to be significantly increased relative to baseline at 1, 5 and 10 min after SAS, thus providing novel evidence for a poststretch hyperaemia. No significant interaction for [HHb] was found between stretching and cycling conditions, suggesting that the metabolic disturbance during stretching closely resembles moderate intensity exercise. These findings suggest that a single self-administered stretch for 60 s can produce a substantial microcirculatory event and that blood flow may be enhanced for up to 10 min after stretching.
authors.affiliation: Cardiopulmonary and Metabolism Research Laboratory, Department of Kinesiology, University of Toledo, Toledo, OH, USA.
authors.forename: Nicholas T
authors.initials: NT
authors.lastname: Kruse
authors.affiliation: Cardiopulmonary and Metabolism Research Laboratory, Department of Kinesiology, University of Toledo, Toledo, OH, USA.
authors.forename: Barry W
authors.initials: BW
authors.lastname: Scheuermann
mesh_terms: D000328:Adult; D001642:Bicycling; D015415:Biomarkers / Q000097:blood; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008833:Microcirculation; D009119:Muscle Contraction; D052580:Muscle Stretching Exercises; D018482:Muscle, Skeletal / Q000098:blood supply / Q000378:metabolism*; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption; D010108:Oxyhemoglobins / Q000378:metabolism*; D011237:Predictive Value of Tests; D011897:Random Allocation; D012039:Regional Blood Flow; D019265:Spectroscopy, Near-Infrared; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin; D010100:Oxygen
keywords: muscle blood volume; muscle oxygen consumption; muscle stretch; near infrared spectroscopy