• Cardiometabolic response to a single high-intensity interval exercise session versus breaking up sedentary time with fragmented high-intensity interval exercise

      Bailey, Daniel Paul; Orton, Charlie J.; Maylor, Benjamin D.; Zakrzewski-Fruer, Julia K. (Thieme, 2019-02-04)
      This study compared the effects of interrupting prolonged sedentary time with high-intensity physical activity (SED-ACT), a volume and duration-matched high-intensity interval exercise session followed by prolonged sedentary time (HIIE), and prolonged uninterrupted sedentary time (SED) on postprandial glucose, insulin and triglyceride concentrations. Twelve sedentary and inactive, but otherwise healthy, adults completed three, 6.5 h conditions in an incomplete counterbalanced order. During SED, participants sat continuously. For HIIE, participants completed 10 x 60 s cycling bouts at 90% maximum oxygen update (V̇O2max) with 1 min active recovery between bouts. In SED-ACT, 60 s cycling bouts at 90% V̇O2max were completed every 30 min (10 times in total) with 30 s of active recovery immediately before and after. Standardised meals were consumed at 0 h and 3 h and capillary blood samples were collected fasted and every 30 min. Compared with SED, postprandial glucose incremental area under the curve (iAUC) was significantly lower in SED-ACT by 1.91 mmol/L∙6.5 h (p=0.022) and triglyceride iAUC was significantly lower in HIIE by 1.02 mmol/L∙6.5 h (p=0.030). Interrupting sedentary time with high-intensity physical activity can lower postprandial glucose concentrations, whereas a HIIE session can lower postprandial triglyceride concentrations.
    • Effects of frequency and duration of interrupting sitting on cardiometabolic markers

      Maylor, Benjamin D.; Zakrzewski-Fruer, Julia K.; Stensel, David J.; Orton, Charlie J.; Bailey, Daniel Paul; University of Bedfordshire (Thieme, 2019-09-09)
    • Effects of interrupting sitting with use of a treadmill desk versus prolonged sitting on postural stability

      Charalambous, Laura H.; Champion, Rachael B.; Smith, Lindsey Rachel; Mitchell, Andrew C.S.; Bailey, Daniel Paul; University of Bedfordshire (Thieme, 2019-10-07)
      High amounts of sitting increase the risk of non-communicable disease and mortality. Treadmill desks make it possible to reduce sitting during the desk-based worker's day. This study investigated the acute effect on postural stability of interrupting prolonged sitting with an accumulated 2-h of light-intensity treadmill desk walking. Twenty-one sedentary adults participated in this randomized acute crossover trial, with two 6.5 h conditions: 1) uninterrupted sitting and 2) interrupted sitting with accumulated 2 h light-intensity treadmill desk walking. Pre- and post-condition, participants performed four postural stability tests on a pressure plate (bipedal and unipedal standing stance, eyes open and eyes closed). Anteroposterior center of pressure amplitude showed a significant condition x time interaction in bipedal eyes closed (F(1,20)=4.62, p=0.046) and unipedal eyes open (F(1,20)=9.42, p=0.006) tests, and mediolateral center of pressure amplitude in bipedal eyes closed (F(1,20)=6.12, p=0.023) and bipedal eyes open (F(1,12)=5.55, p=0.029) tests. In the significant interactions, amplitude increased pre to post condition in the uninterrupted sitting condition. The accumulated 2 h light-intensity treadmill desk walking ameliorated the negative effect of 6.5 h prolonged sitting on postural sway, supporting workplace treadmill desk use.