New research from the Team lead by Dr Thomas Wilkinson: People with a kidney condition may need to exercise differently

A new study published by our team in the journal Kidney Research in Clinical Practice called ‘Response of the Oxygen Uptake Efficiency Slope to Exercise Training in Patients With Chronic Kidney Disease’ showed that 12-weeks of exercise may have a limited effect on the fitness in people with a kidney condition.

People with a kidney condition have poor fitness levels which can be improved through regular exercise. However, in other studies we have done we have noticed that not all people improve their fitness by doing exercise. We think this could be because of problems in the muscles. It may also be due to the way we measure fitness. The best way to test fitness is through something called a ‘maximal cardiopulmonary exercise test’. This involves measuring the maximum amount of oxygen our bodies can use during exercise. This is often done by cycling on a static bike wearing a special mask that can measure oxygen and carbon dioxide in our breaths. This test can get very difficult as the resistance on the bike increases and many people stop the test early due to different reasons such as tiredness, pain, or lack of motivation. If the test is stopped early, then we do not get an accurate picture of what someone’s maximum fitness is.

To get around this we looked at something called the oxygen uptake efficiency slope (OUES). Rather than looking at the oxygen at the end of the fitness test, this slope is measured by assessing how a person’s need for oxygen changes during the test. This is a more pragmatic and safer alternative to maximal testing and does not rely on maximum effort by someone doing the test.

We looked at 32 people with CKD who underwent a 12-week exercise program consisting of mixed aerobic and strength training three times a week. The fitness test was conducted before and after the exercise. We saw no changes were observed in any fitness variable as a result of exercise. This includes analysis of the oxygen uptake efficiency slope.

Our results show that 12 weeks of exercise training had no beneficial effects on the fitness levels of people completing the study. This could mean that people do not respond to exercise as well as those without kidney disease. It could also mean that people need to do exercise for longer (than 12-weeks) to see an effect. This shows that regular exercise is important for people with a kidney condition.

A link can be found here to the scientific article:  https://pubmed.ncbi.nlm.nih.gov/32550710/

The researchers involved in the study were Dr Thomas J Wilkinson, Dr Emma L Watson, Noemi Vadaszy, Dr Luke A Baker, Prof João L Viana, Prof Alice C Smith.