Introduction
Exercise is a well-documented preventative and therapeutic intervention for both the risk of, and management of type two diabetes (1). Many populations are unable to exercise, which may contribute to a greater risk of type two diabetes. For example, type two diabetes prevalence in the spinal cord injury (SCI) population is 2.52 times greater than the general population (2). Populations which are unable to exercise, such as those with SCI, are unable to access conventional exercise.
Therefore, it is imperative that effective alternatives to conventional exercise are investigated as methods of achieving greater glycaemic control compared to an exclusively sedentary lifestyle. Passive movement training (PMT) may be beneficial in this regard as increased skeletal muscle blood flow has been demonstrated to be associated with greater glucose uptake from the blood to muscle during acute exercise (3). This may also apply to PMT.
This crossover study examines the effectiveness of PMT, with and without blood flow restriction (BFR), at minimising postprandial glucose excursions compared to that at rest.
Methods
Prior to recruitment and data collection, ethical approval was obtained from Lancaster University’s Faculty of Health & Medicine Research Ethics Committee (FHM-2024-4434-SA-2). The trial was pre-registered at ClinicalTrials.gov (NCT06704126). The trial has been conducted in accordance with the latest version of the Declaration of Helsinki.
Seven healthy males (mean ± SD) (aged 25.3 ± 6.4 years; height 1.80 ± 0.1 m; weight 82.2 ± 9.9 kg; BMI 25.4 ± 2.3 kg/m2) completed three 150-minute visits to Lancaster University’s Human Performance Laboratory in a fasted state. Fasted blood glucose and insulin measures were obtained immediately prior to a standardised meal being consumed (energy 522 kcal; carbohydrate 112.5g; of which sugars 51.6g; protein 6.9g; fats 4.0g; fibre 3.3g).
Once 30 minutes had elapsed from fasting measurements, either PMT only, PMT + BFR or control (CTRL) protocols commenced for 30 minutes. The PMT elements were conducted using an isokinetic dynamometer (S3, Biodex, New York). These were conducted in a randomised sequence in each participant. A further 90-minute period of glucose and lactate monitoring followed. Throughout the session entirety, venous samples were drawn at five-minute intervals via an antegrade fitted cannula, and glucose and lactate concentrations were analysed.
Preliminary results
Differences in glucose area under the curve (AUC) during the final 120 minutes were analysed by way of a repeated measures ANOVA. No significant differences were observed between CTRL, PMT or PMT+BFR treatments (CTRL 522.8 ± 95.9 mmol min/L, PMT 512.1 ± 96.4 mmol min/L, PMT+BFR 483.9 ± 137.2 mmol min/L (p = 0.612).
Conclusion
These preliminary results suggest undertaking PMT or PMT+BFR training have no significant effect on post-prandial blood glucose excursion. This may be due to insufficient blood flow being present to allow an observed effect, a lack of demand for skeletal muscle glucose uptake or insufficient participants to allow a significant effect to be seen at present. Further glucose excursion data and insulin analyses will be presented via conference once data collection is complete.