The Benefits of Exercise in Chronic Renal Disease

In this day and age, we are so used to reaching for a pill to solve all our health problems that we forget that there are plenty of other interventions that we can implement to prevent, slow down and even improve the outcome of many chronic diseases, including chronic kidney disease. Exercise is one of these amazing things that we can add to our routine and the best bit is that it costs nothing to get started! 

A nice basic definition of exercise is the training of the body to improve its function and enhance its fitness. Pretty straightforward forward right? 

What types of exercises are the best, and how long should I train for? Are there any things that I need to avoid or look out for if I have kidney disease?

Read on to find out the answers…

When you are diagnosed with a chronic disease it is easy to feel that all you want to do is hide away from the world and not interact with it. I know! But having been diagnosed with a chronic disease I can tell you one of the best things that I ever did to improve my health outcomes was to start exercising.

I have always been super fit and active, I was a track champion in high school, and I played sport all the way through school and in my years at uni. I took up weight training (something I still do four times a week now), I started hiking, running a few times a week and of course riding my horses daily, which kept me super fit. But after a fall off my horse in 2015, which set my Multiple Sclerosis off to the point that I could no longer run and walking became harder than I would like, I lost the ability to participate in all the activities and sports that I loved so much! Now I could have crawled in a hole, and felt sorry for myself and stayed there, trust me I thought about feeling sorry for myself for a long time, but what good was that going to do me? So instead of crawling into a comfortable hole, I decided I would modify my exercise regime to incorporate things that I could do and things that I still enjoyed. For me, that was weight/resistance training. 

Why was I so eager to keep exercising as part of my regime? Let me explain.

Exercise Reduces Inflammation

Now if you have been reading our blogs and listening to our YouTube videos you will know that inflammation is the driver of most of our modern Western diseases, including Kidney disease, heart disease, diabetes, and in my case Multiple Sclerosis. 

Exercise has the ability to reduce inflammation in a variety of ways:

• Reduces fat mass and adipose tissue inflammation which is known to contribute to systemic inflammation
• Exercise also increases muscle production of IL-6 which is known to reduce TNF-α production and increase anti-inflammatory cytokines.
• Exercise increases circulating levels of IL-10 and IL-1 receptor antagonists, both anti-inflammatory cytokines.
• It increases circulating numbers of IL-10-secreting regulatory T cells
• Improves Toll-like receptor expression on monocytes and inhibition of downstream responses (such as pro-inflammatory cytokine production, antigen presentation, and co-stimulatory molecule expression)
• Reduction in the circulating numbers of pro-inflammatory monocytes
• Inhibiting the signalling effects of a protein called interleukin 1 beta, which triggers inflammation that can damage the cells in the pancreas that produce insulin.
• The basic non-technical version of the above is basically exercise reduces inflammatory cytokines and promotes anti-inflammatory cytokines that lead to an overall down-regulation of inflammation throughout the body. It also improves and protects the pancreas which may, in turn, reduce the onset of type II diabetes. 

Exercise Improves Insulin Sensitivity

By now I am sure that you know that diabetes is one of the two leading causes of chronic renal failure. So it makes sense that anything we can do to manage blood glucose levels will have a positive flow-on effect on kidney health.

• Regular exercise makes your muscles utilize insulin more effectively. This in turn leads to better blood sugar regulation and control by the pancreas.
• Exercise lowered HbA1c values by 0.7 percentage points in people of different ethnic groups with diabetes who were taking different medications and following a variety of diets, and this improvement occurred even without any weight loss.
• Resistance training and aerobic exercise both helped to lower insulin resistance in previously sedentary older adults with abdominal obesity at risk for diabetes. Combining the two types of exercise proved more beneficial than doing either one alone.
• People with diabetes who walked at least two hours a week were less likely to die of heart disease than their sedentary counterparts, and those who exercised three to four hours a week cut their risk even more.
• Women with diabetes who spent at least four hours a week doing moderate exercise (including walking) or vigorous exercise had a 40% lower risk of developing heart disease than those who didn’t exercise. These benefits persisted even after researchers adjusted for confounding factors, including BMI, smoking, and other heart disease risk factors.

Exercise Reduces Blood Pressure

Blood vessels dilate and become less stiff as your heart beats faster and harder. The vessels stretch and accommodate the excess pressure to keep blood pressure under control. During exercise, the heart pumps harder and blood pressure rises modestly, but the blood vessels become more elastic, which can help and even prevent hypertension.

Regular exercise improves heart muscle function, like any muscle when it is used more the muscle gets stronger, a stronger heart can pump blood more effectively around the body, which in turn leads to a decrease in blood pressure.

• Exercise improves circulation
• Exercise makes the blood vessels more elastic and less stiff which in turn helps to bring down blood pressure.
• Studies show regular exercise helps reduce the risk of coronary heart disease by as much as 21 per cent for men and 29 per cent for women. Additionally, active people have a 20 per cent less chance of stroke.

https://www.ahajournals.org/doi/10.1161/hypertensionaha.112.197780

Exercise Improves Cholesterol Status

While the exact mechanism of how exercise improves cholesterol levels and ratios is unclear, exercise appears to enhance the ability of skeletal muscles to utilize lipids as opposed to glycogen, thus reducing plasma lipid levels as a result.  It is thought to do this via a mechanism that increases lecithin-cholesterol acyltrans (LCAT), which has been shown to increase following exercise training.

The process of cholesterol removal is known as ‘reverse cholesterol transport. This process removes cholesterol from circulation for disposal as a result of increases in LCAT and reductions in cholesterol ester transfer protein (CETP).

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3906547/

In layman’s terms:

• Exercise helps increase levels of HDL, a good type of cholesterol. 
• Exercise may even change the nature of our cholesterol. In 2002, researchers from Duke University Medical Center found that exercise improved the number and size of the particles carrying cholesterol through the body. Those who exercised more had larger, “fluffier” particles that were less likely to clog arteries. See our article on why size matters when it comes to cholesterol to understand this more. 
• Exercise can help you lower cholesterol numbers even if you’re overweight. In the Journal of Obesity, researchers reported that overweight and obese adults who walked, jogged, and cycled while eating a cholesterol-lowering diet improved total cholesterol, LDL cholesterol, and triglyceride levels.
• A meta-analysis of 11 studies published in November 2018 in the journal BioMed Research International found that after 8 to 24 weeks of low- or moderate-intensity exercise for 30 to 40 minutes a day, participants had lower LDL (bad cholesterol)  cholesterol levels in some studies, as well as lower LDL subfractions (associated with heightened cardiovascular disease risk) in others.

Exercise and Kidney Disease

A very recent study published this year in 2021 of 108,615 participants aged 18 years or above, found that higher habitual exercise was associated with lower risks of renal function decline and CKD development.

https://www.sciencedirect.com/science/article/abs/pii/S1438463921001061

Another study published this year in 2021 found that cardiorespiratory fitness improves mortality risk prediction among patients with chronic kidney disease. 

https://www.sciencedirect.com/science/article/abs/pii/S000293432100560X

A 2017 paper found that exercise is helpful in ameliorating the situation of blood pressure in patients with renal failure and significantly reduces VO2 in patients with renal failure. The results of subgroup analyses show that, in the age >50, physical activity can significantly reduce blood pressure in patients with renal failure. 

https://pubmed.ncbi.nlm.nih.gov/28316986/

A study looking at implementing exercise programs for those with advanced chronic kidney disease and those on dialysis found a positive association between exercise and improvement of many targets in chronic kidney disease, especially in dialysis patients, such as cellular apoptosis, immune improvement, and inflammation.

https://pubmed.ncbi.nlm.nih.gov/32186605/

A metaanalysis done in 2019 found that data from 27 studies with 1,156 participants showed that exercise, regardless of modality, generally increased 6-min walk test distance, sit-to-stand time or repetitions, and grip strength as well as step and stair climb times or repetitions, dynamic mobility, and short physical performance battery scores. From the evidence available, exercise, regardless of modality, improved objective measures of physical function for end-stage kidney disease patients undergoing dialysis.

https://pubmed.ncbi.nlm.nih.gov/30759022/

Other Benefits of Exercise

Apart from all the amazing benefits of exercise that I have mentioned above exercise has also been shown to:

• Slow and reduce cognitive decline
• Improve immune function
• Improve bone density and reduce the risk of osteoporosis
• Reduce the risk of falls
• Improve sleep quality
• Improve muscle mass
• Reduce chronic illness leading to people becoming bedridden
• Reduce the impacts of stress on the body

Best Time to Exercise

The best time to exercise is 30 mins to 2 hours after a meal. Exercising in this window is the best way to improve insulin sensitivity and blood sugar regulation, which in turn helps to combat the effects of diabetes.

Try to avoid exercising too close to bedtime as this may actually negatively impact your sleep quality. 

What Type of Exercise Should I Do?

If you are new to exercising and just getting started then find something that you enjoy. That is the best way to ensure that it becomes a lasting habit rather than a short-term fad. Some great ways to get started include:

• Hiking
• Dancing
• Yoga
• Pilates
• Swimming
• Resistance training
• Aqua aerobics
• Bike riding

Keeping exercise as an ongoing inclusion in your life can often be the most challenging part. We often start off with the best intentions and then lose interest. This happens often due to doing something that you don’t enjoy or setting up too high expectations for yourself so it feels too hard. For me, I keep exercise as a part of my routine by having personal training that keeps me accountable! Plus having an appointment means I am so much more likely to go to the gym. If I just went to the gym and trained myself, which I am more than capable of doing if I was tired or just not up to it I just wouldn’t go. Having a personal trainer means I show up, and I am always glad that I do! Duncan exercises by dancing, which he loves. So choose something that you love to get started. The more you build your fitness the more new types of exercise you will feel confident to try. Better yet get an accountability partner to start exercising with you, that makes it social and fun!

Saunas

A quick word on saunas. For some of my patients jumping into an exercise routine is just not doable, this may be due to them being obese, having a heart condition, or injury. Saunas are a great way to start the weight loss journey before undertaking traditional exercise. Saunas replicate what happens to the heart when we do a cardio workout. Saunas hold many of the same benefits as pure exercise. Just make sure you drink plenty of water and shower immediately after you finish, as you will sweat out toxins onto the surface of your skin that you want to wash off so you don’t reabsorb them back through your skin and into your blood.

If you have a preexisting heart condition talk to your GP or health care professional first before starting saunas and make sure you start slowly.

Final Words

Hopefully, you can see the many amazing benefits of exercise and how incorporating it into your daily routine may have many lasting benefits. As always if you have any concerns please talk to your healthcare professional or engage the services of a qualified trainer.

Exercise, when done properly, is fun and helps build resilience as well as self-confidence. For me, it has the greatest positive impact on my health over anything else I do. So if you have been wondering what other things you can do to improve your kidney function exercise should be on your list.

Let us know what type of exercise you enjoy by heading over to our Facebook page and leaving us a comment, I am sure others in our community would love to hear how you keep fit.