Currently most countries around the world have enacted self-isolation and quarantine rules to help flatten the curb and reduce the spread of COVID-19. An unfortunate by-product of these restrictions has been the closure of gyms and fitness studios, coupled together with a large number of people now working from home. This has made exercising more challenging and reduced people’s motivation to exercise resulting in more sedentary behaviour and reduced physical activity.

At present the physical activity guidelines recommend at least 150mins per week of moderate to vigorous activity. This means exercising at least to a level where you are unable to complete a full sentence without taking a breath. Why is physical activity important? There is a growing body of evidence that shows how beneficial exercise is for a raft of conditions, it helps to reduce your risk of developing chronic preventable diseases like diabetes, obesity and cardiovascular disease, as well as reducing your risks of certain types of cancers including breast, colon, liver, kidney. Additionally, it is beneficial for improving balance, bone health, quality of life, cognition, sleep, mood, mental health and immunity among others. 

To combat this decline in physical activity and to motivate people to keep exercising throughout the COVID-19 pandemic, the Shannon Clinic together with the help from some great friends who are professional athletes, we have started the #getmoving initiative. On the Shannon Clinic Instagram page we are dropping a series of videos every few days this week from pro athletes who are here to encourage you to keep exercising and to show you how easy it is to exercise without access to a gym or equipment.

We hope that you enjoy the videos as they are released, and they motivate you to keep exercising, we also ask you to share the videos and if you have any requests or questions please comment below the posts. Ultimately, we would like spread the word as far and wide as possible and would like more pro athletes to post similar videos of encouragement. I thank my wonderful friends including WTA players Demi Schuurs and Nicole Melichar, Brazilian Jiu Jitsu champion Ben Hall, ATP players Bruno Soares and Alex Peya for helping out, so get out there and get moving!

With the current COVID-19 pandemic creating global disruption, uncertainty and with many countries enforcing society lockdowns, it is making physical activity and exercise more onerous. However, one of the few exceptions to the lockdown rules is exercise, so lets examine the evidence on exercise and immune function.

It is well known that regular bouts of exercise lasting up to 45 minutes of moderate to vigorous exercise is beneficial for immune defence, particularly in older adults and those with chronic diseases. This type of exercise is beneficial for the normal functioning of the immune system and is likely to help lower the risk of respiratory infections/illnesses. However, there is debate within the scientific community whether acute bouts of vigorous intensity exercise leads to a period of immune suppression post exercise.

There has been a long held concept in exercise immunology developed in the 1980s and 1990s called the “open window” hypothesis which proposes a J curve relationship between exercise intensity and infection risk. Which is supported by the belief that athletes who engage in high volume endurance training experience a greater incidence of Upper Respiratory Tract Infections (URTI) compared to those who are less active. Until recently this concept has remained relatively unchallenged.

The “open window” hypothesis suggests that following a prolonged (>1.5hr) and vigorous acute bout of exercise or following chronic intense training (>1.5hr on most days) there is an “open window” which results in an increased risk of opportunistic infections such as URTI’s. The three principles underpinning this concept are:

1). Infection risk increases after prolonged vigorous aerobic exercise

2). Acute bouts of vigorous exercise can lead to temporary reductions in salivary immunoglobulins resulting in higher risk of opportunistic infections

3). A period of post exercise reduction in peripheral blood immune cells resulting in a period of immune suppression.

J Curve – relationship between the risk of infection and level of exercise intensity

Recently though there has been emerging evidence suggesting this concept may be outdated. There is evidence, albeit small that indicates international athletes suffer from less URTI than national athletes. This raises the likelihood that infection susceptibility is more likely multifactorial including genetics, sleep, stress, nutrition, travel, circadian misalignment and increased exposure risks due to close proximity of crowds rather than being directly attributed to acute or chronic bouts of vigorous training. This also indicates that international athletes are potentially better supported, have access to better education helping them to improve their life-style behaviours over national athletes resulting in lower risks of infection.

Secondary to this, evidence supports the opposite of the three principles upholding the “open window” concept. With no changes seen in mucosal immunity which has previously been flagged as an indication of immune suppression. The reduction in blood immune cells (primarily lymphocytes) 1 to 2 hours post exercise reflects a transient and time dependent redistribution of immune cells to peripheral tissues resulting in a heighten state of immune surveillance and regulation leading to enhanced antibacterial and antiviral immunity, not suppression of the immune system.

Further research is needed to confirm or refute the “open window” concept however, it currently appears that the infection risk post vigorous exercise is more likely to be associated with a multitude of other factors rather than purely post exercise immune suppression. So for athletes and non-athletes the message remain the same during COVID-19, regular moderate to vigorous exercise is beneficial to enhance immune function to reduce the risk of bacterial and viral infections including URTI’s. And remember that good hygiene practices (washing hands regularly, not touching your face), physical distancing, getting good quality sleep, reducing stress levels and eating healthy wholefoods are the keys keeping your immune system in peak condition.

Find out more information on COVID-19 here.

When people talk about the keys to living a healthy life and performing at your best, exercise and diet are always front and centre. Rightly so, as exercising at least 150 mins per week at moderate to vigorous intensity and eating a well-balanced diet rich in green leafy vegetables, fruits, grains and seafood and low in red meats and saturated fats are essential for longevity and a healthy life. But there is a third pillar that is regularly overlooked that is just as important as diet and exercise and that is sleep.

Sleep Deprivation

Sleep deprivation can be due to sleep disorders like insomnia and sleep apnoea. These disorders are often associated with symptoms such as difficulty falling asleep or maintaining sleep and require further clinical investigation. However, most sleep deprivation occurs due to poor sleep quality and duration. The average adult requires 7-9h of sleep per night yet those with sleep deprivation will get less than 5-6h of sleep per night. Some people pride themselves on their ability to work with very little sleep yet sleep deprivation has been shown to affect human (and athletic) performance in a myriad of ways including:

  • Impaired cognition effecting decision-making, judgment, mood, and reaction times
  • Metabolic disruption including diabetes and obesity
  • Weight gain to due craving more unhealthy and high carbohydrate foods and in larger portions
  • Immunological resulting in increased proinflammatory cytokines which impair immune function and impede muscle recovery and repair from damage
  • Cardiovascular dysfunction
  • An increased risk of injury

There is also a dose-dependent relationship between sleep and performance; the greater the sleep loss the greater the performance loss, with performance loss occurring with as little as 2-4h of sleep loss. And for those who believe they are able to recoup the sleep they lose during the week on the weekends, the evidence says the contrary.

Improving Sleep Quality and Duration

The two sleep interventions that have received most research are sleep extension and sleep hygiene. Sleep extension and napping involves extra sleeping time to make sure the 7-9h daily limit is being met; this is especially useful when one knows they have a day of potential sleep deficit ahead. Sleep extension might involve going to sleep earlier or utilization day time naps that are more than 20 mins but less than 60 minutes and occur before 3pm. Sleep hygiene helps to improve sleep quality and duration and essentially involves a healthy sleep routine such as:

  • Don’t go to bed if you aren’t sleepy
  • Rise at the same time every morning, including on the weekends
  • The bed is for sleeping only, don’t watch TV or use electronic devices in bed
  • Avoid caffeine after lunch
  • Avoid alcohol, especially before bed
  • Avoid high intensity interval training before bed
  • Try to create a dark, quiet and cool space to sleep (ambient temperature is 19+/-2 degrees)

Improvements in sleep extension can lead to improved skill specific execution in sports, improved cognition including reaction times. mood, alertness and vigor. While improved sleep hygiene results in less fatigue and sleepiness.

Whether the goal is optimizing performance at work, in sport or about doing all you can to live a healthy life, sleep needs to be given as much attention as diet and exercise. By improving the quality and duration of sleep through better sleep hygiene and sleep extension one will yield benefits such as, reducing the risks of preventable disease like diabetes, obesity, cardiovascular disease, improved judgment and decision-making and optimized athletic performance and recovery.

Sedentary behaviour and your health

It might seem strange to hear the average working week in Australia has reduced by 2 hours per week however, that doesn’t mean people are working less, it purely represents a shift from productivity to outcome based performance measurements. Tied together with the development of new technologies and the introduction of flexible working options including working from home, it means workers days are stretched longer, they are available more of the time and are working more hours they don’t register. Ultimately this leads to more sedentary behaviour at work.

Interestingly, the first occupational study looking at health outcomes in those who were physical active at work versus those who weren’t was published way back in 1951. The Morris paper looked at the rates of coronary heart disease (CHD) in bus drivers compared to ticket conductors and it was no surprise to see bus drivers had a higher incident of CHD compared to ticket conductors. To confirm these findings Morris and Crawford then compared the risk of heart attacks between postmen and government clerks and found a similar result; government clerks more often suffered heart attacks than postmen.

Fast-foward to 2019 where we now know that sedentary behaviour is associated with higher blood pressure, total cholesterol and poor cognition and academic performance. It is also strongly associated with all cause mortality, fatal and non-fatal cardiovascular disease, type 2 diabetes, metabolic syndrome along with being moderately associated with ovarian, colon and endometrial cancer.

Time to get moving!

As Morris showed in his studies, workers who were more active had lower incidents of cardiovascular disease (CVD) and this rings true today. In 2018 the Physical Activity Guidelines Advisory Committee Scientific Report highlighted the importance of physical activity which is linked to improved sleep, cognition, minimizing weight gain, reduced risks of depression, anxiety, dementia, colon, breast, bladder, endometrial, oesophagus, stomach, kidney and lung cancer as well as reduced risks of chronic preventable diseases like high blood pressure, type 2 diabetes and cardiovascular disease. There is also low grade evidence indicating sit to stand desk (ie. being more active) reduces low back pain in office workers.

Breaking up sedentary behaviour doesn’t need to be difficult, it might involve introducing a sit to stand desk to help modulate posture throughout the day, getting up from the desk and walking around the office at regular intervals, it could include exercising during the lunch break and for the extremely busy people think about replacing your car commute to work with a ride or run. Whatever it is you chose to break up your sedentary behaviour with, it is important that you are reaching the minimum guidelines for physical activity – 150 minutes of moderate to vigorous activity per week.

Lets talk about diets, as every other week there is a news article talking about the “best” diet for weight loss. There is the high protein diet, the low carbohydrate ketogenic diet, there are experts who say dieting doesn’t work, bloggers spruiking the benefits of the intermittent fasting diet, Instagram influencers telling us the key to weight loss is exercise, and of course it wouldn’t be complete without the latest celebrity diet.

Which Diet Is Best?

With all of this information it is hard to know who is right. In 2014 a meta analysis looked at a variety of diets to see how they compared against each other in relation to weight loss. They compared popular diets like the Atkins, Zone, Weight Watchers and Jenny Craig diets in overweight and obese adults. After 12 months, they found no difference between the diets, with all diets resulting in weight loss.

What about the argument that a well balanced diet is the key? A meta analysis in 2014 compared obese and overweight adults with and without diabetes, who were assigned either a balance diet or a low carbohydrate diet. There were no differences in weight loss between the groups, nor any differences in blood pressure, cholesterol, triglycerides, low-density lipoproteins and high-density lipoproteins (bad and good fats).

Is Exercise The Key To Weightloss?

How about exercise then, with the rise of social media there are plenty of “influencers” promoting their own weight loss exercise regimes, could it be they are right? Unfortunately not, the importance of exercise in weight loss is one of the greatest misconceptions. 100% of our energy intake comes from food, yet only 10-30% can be burned through physical activity. Physical activity is extremely important and is associated with a multitude of health benefits, however for weight loss it is only one piece of the puzzle.

Which Diet Is Best For Me?

About now the question becomes, “if there are no differences between diets and exercise doesn’t contribute greatly to weight loss, then what is the best way forward?” The key to losing weight is adherence. Adhering to a nutritional regime that can be stuck to long term. Low carbohydrate diets and low carbohydrate Mediterranean diets are great for weight loss, especially in obese diabetic individuals, however if it can’t be adhered to long term the weight will return. This behaviour pattern of short term weight loss followed by longer term weight gain is consistent with most weight loss diet research.

If your goal is to lose weight long term, forget the latest fads, ignore social media, and stick to the following key principles.

  • Choose a diet you can adhere to long term
  • Aim for a 100 calorie per day energy deficit
  • Stick to low GI plant based carbohydrates
  • Eat minimally processed foods
  • Include wholegrains
  • Lower your fat intake
  • Choose a form of exercise you will adhere to
  • Join a support group
  • Consider weighing yourself daily

The American College of Rheumatology and the American College of Orthopaedic Surgeons recommend opioids such as Tramadol as a front line intervention for knee osteoarthritis (OA), either on their own or in association with NSAID’s.

This paper looked at the 1 year all cause mortality risk associated with knee OA and the use of opioids (Tramadol and Codeine) compared to NSAID’s. Over 1 year the risk of all cause mortality was higher in those who used opioids compared to NSAID’s. This presents a strong case that opioids shouldn’t be used to treat knee OA. However, it must be pointed out that this paper didn’t confound for risks such as cardiovascular disease, diabetes, obesity etc which are commonly seen in patients with knee OA and can be associated with all cause mortality. Therefore further research is required to better understand these results.

Having said that, there is good evidence that supports the use of exercise therapy for improvements in pain and function associated with knee OA. Therefore a more appropriate front line intervention would be to avoid opioids and to utilise exercise therapy and NSAID’s when needed to treat knee OA.