Effects of knee extension with different speeds of movement on muscle and cerebral oxygenation

• DOI: 10.7717/peerj.5704
• Publication Date: 2018-10-02T04:11:05Z
• Authors: Damiano Formenti; David Perpetuini; Pierpaolo Iodice; Daniela Cardone; Giovanni Michielon; Raffaele Scurati; Giampietro Alberti; Arcangelo Merla
• Keywords: Vastus lateralis muscle; Deoxygenated Hemoglobin

One of the mechanisms responsible for enhancing muscular hypertrophy is high metabolic stress associated with a reduced oxygenation occurring during exercise, which can be achieved by reducing speed movement. Studies have tested that lowered muscle artificially induced an inflatable cuff, could provoke changes in prefrontal cortex oxygenation, hence, to central fatigue. It was hypothesized (1) exercising slow movement would result greater increase cerebral and decrease compared exercises faster (2) amount ipsilateral lower than contralateral one.An ISS Imagent frequency domain near infrared spectroscopy (NIRS) system used quantify vastus lateralis (contra- ipsilateral) unilateral resistance different speeds voluntary After one maximal repetition (1RM) test, eight subjects performed three sets knee extensions (∼50% 1RM), separated 2 min rest periods, following pace 1 s, 3 s 5 both concentric eccentric phases, random order, separate sessions. The change NIRS parameters (ΔHb: deoxyhemoglobin, ΔHbO: oxyhemoglobin, ΔHbT: total hemoglobin, ΔStO2: oxygen saturation) were quantified between conditions two-way ANOVA RM. Differences contra- (lobe) tested.Exercising larger deoxygenation normal movement, as revealed significant interaction (set × condition) ΔHb (p = 0.01), main effects condition ΔHbO 0.007) ΔStO2 0.016). With regards cortex, lobe showed ΔHb, ΔHbO, ΔHbT, each set (main effect lobe: p < 0.05). Main only set1 all parameters, found 0.05).These findings provided evidence influences oxygenation. Since lack increased stress, manipulating may useful planning resistance-training programs. Moreover, consistent increases right left lobes found, suggesting complementary ipsi- also seems related