Publications by authors named "A J Johnstone"

Objective: In this feasibility study, firstly, we aimed to assess whether intramuscular pH (IMpH) could be measured with a glass-tipped electrode. Secondly, we aimed to explore whether we could monitor changes in skeletal muscle pH before and throughout static (isometric) and after dynamic (treadmill) exercise, comparing individuals with intermittent claudication (IC) to a group of healthy controls.

Methods: Forty participants with IC (mean age ± SD) 68 ± 8) and 40 healthy volunteers (63 ± 10) were recruited.

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Experimental inversion of circadian and behavioral rhythms by 12 h adversely affects markers of metabolic health. We investigated the effects of a more modest 5-h delay in behavioral cycles. Fourteen participants completed an 8-day in-patient laboratory protocol, with controlled sleep-wake opportunities, light-dark cycles, and diet.

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The high prevalence of food insecurity in the United Kingdom has been exacerbated by the cost-of-living crisis. In high-income countries, those experiencing food insecurity struggle to buy and consume foods that meet Government healthy eating recommendations, and are at increased risk of obesity, linked to poor diet quality. Individuals in high-income countries purchase most of their food to consume at home from supermarkets, making this an important context within which healthier and environmentally sustainable food purchasing should be supported.

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Chrono-medicine considers circadian biology in disease management, including combined lifestyle and medicine interventions. Exercise and nutritional interventions are well-known for their efficacy in managing type 2 diabetes, and metformin remains a widely used pharmacological agent. However, metformin may reduce exercise capacity and interfere with skeletal muscle adaptations, creating barriers to exercise adherence.

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