Why people in physically active jobs still need to exercise…

As someone who sits in front of a laptop all day, I often wish for a more “active” job. In fact, sedentary jobs are considered to be a significant contributor to the obesity epidemic and many related health problems in western countries. In an attempt to counter this, many tools such as treadmill desks and walking meetings have been implemented in the workplace. It seems then, if you had an active job, like one in construction let’s say, that you might be able to counter this problem. Turns out, it isn’t that simple.

While an active job certainly does lead to an increase in energy expenditure (the number of calories burned), it doesn’t necessarily lead to an increase in fitness or health. In a recent study published in the peer-reviewed journal, British Journal of Sports Medicine, Holtermann and colleagues set to investigate whether having an active job had the same benefit as being physically active in your spare time. They used long-term absence from work as a health indicator. Using a large Danish database, they categorized people into 4 groups based on the activity they did at work and 4 groups based on the activity they did in their spare time. Taking into consideration a variety of factors such as smoking, chronic disease presence, emotional demands and education, the researchers found that more active jobs were associated with MORE long-term absence from work while more physical activity in spare time was associated with LESS long-term absence from work. This was true for both males and females.

Surprised? It is contrary to what we would expect. As an exercise scientist I always say that “any activity is good activity”. It seems I should re-adjust this to “any leisure-time activity is good activity”!

The findings of the study are actually quite simple to explain. A physically active job is usually very specific. For example, if I were a delivery person, I would be doing the same lifting type of activity all day. This repetitive nature of active jobs often leads to injury. This injury of course can become severe over time and thus lead to absence from work. Interestingly though, if you were to go on a fitness program that strengthened your muscles, particularly of the back and legs, you may not end up having getting these injuries. On the same note, if you did a complete exercise program i.e. cardio and weight training and stretching, then you are less likely to sustain other injuries at work and will reduce your risk of chronic conditions. In other words, while those few repetitive tasks you do at work are burning calories, they aren’t doing much for your overall health or fitness levels.

TAKE HOME MESSAGE: Whether you work in an active job or a sedentary job, it is important to incorporate a balanced exercise program into your life. This can prevent you from sustaining injuries in the workplace and of course it will decrease your risk of chronic disease and improve your quality of life. Remember, any leisure-time activity is good activity, so don’t get too bogged down by what to do!

And of course, don’t forget, you have control of your HALF!!



Can a proper warm-up prevent exercise-induced asthma symptoms?

An appropriate warm-up has long been considered an effective means to prevent exercise-induced asthma (EIA). EIA is a condition in which individuals have symptoms such as breathlessness, sore throat, wheezing and cough after exercise (sometimes during). These symptoms are related to a narrowing of the airways and occur in about 90% of people who have been diagnosed with asthma; it also occurs in many individuals who do not have asthma. If you have experienced these symptoms, consider speaking to your doctor for appropriate diagnosis and treatment.

The reason you usually will not experience EIA during exercise is that during exercise we release Epinephrine or Adrenaline, a hormone that binds to certain receptors in our airways and causes them to dilate (become wider). Once you stop exercising and the levels of epinephrine go down, a person with EIA will generally start to experience symptoms. Here is the great part,  after exercise many people with EIA will go into what is referred to as a “refractory” period and therefore cannot have EIA symptoms for a couple of hours after this session. The question that arises is: what type of warm-up will trigger this protective refractory period?

While several studies have been conducted in this area, there are a variety of warm-up protocols that have been used. In an attempt to clarify the optimal warm-up to prevent EIA, Stickland and his colleagues conducted a review of scientific studies. They reviewed 7 trials with a total of 128 participants. Four types of warm-ups were reviewed: short sprints or intervals, continuous high-intensity, continuous low-intensity and variable intensity (continuous followed by interval). Using lung function (the openness of the airways) as their main criteria, they found that the interval type of warm-up was the most effective at preventing EIA. The interval type warm-up usually consisted of 30 second sprints at a high intensity (all out running for 30 seconds). The number of times to repeat this varied from 8-10 with anything from 45 seconds to 5 minutes between sprints. Finally, the exercise session was conducted 15-20 minutes after doing the interval warm-up.

TAKE HOME MESSAGE: If you have EIA and are struggling with symptoms during exercise, try doing a few 30 second high intensity interval sprints before going to the gym or the track. You can do them around your house or on your walk over to the gym. You can even run up and down the stairs of your house or the hallways of your apartment building. This will ensure that once you get to your workout, you will be in your refractory period! Another important note, if this seems like too much, the use of a bronchodilator (puffer) about 15 minutes before exercise also prevents EIA.

Whether it is an appropriate warm-up or a bronchodilator, do what you need to maintain your exercise and active lifestyle. Don’t forget, you have control of your HALF!!


Can you be healthy if you are obese?

It seems like a paradox. The notion that obese people can be healthy is completely contrary to any public health message we have ever seen, yet, there is increasing evidence that SOME obese individuals may be just as healthy as their normal weight peers.  The question that arises then is: what is it about being obese that makes a person “unhealthy”?

The simple answer to this question is that obesity is associated with a higher risk of cardiovascular disease, type II diabetes, cancer and early death. This is primarily because people who are obese generally have a poor diet and low physical activity levels; they might also consume more alcohol. In other words, the lifestyle that is leading to their obesity is also leading to higher cholesterol, blood pressure, blood glucose levels etc. These of course are primary risk factors for the above mentioned diseases.

Recent research indicates however, that just because someone is obese it does not necessarily mean that they have these risk factors. In a study published in the Canadian peer-reviewed journal, Applied Physiology, Nutrition and Metabolism, Dr. Kuk and her colleagues used a large database (Aerobics Centre Longitudinal Study) to establish just this. They used the Edmonton Obesity Staging System (EOSS), a risk-stratification system that classifies obese individuals using health indicators on a scale of 0-4 with 0 being low risk and 4 being high risk. Using over 20 such indicators, Kuk and colleagues found that only obese individuals in stage 2 or 3 (they were unable to assess stage 4 because of limitations in the dataset) were at an increased risk of death, cardiovascular disease and a variety of other conditions. In other words, there were some obese people (those in stage 1) who were not at a higher risk when compared to normal weighted people. Interestingly, this was not the case for cancer. Regardless of which stage the obese individual was in, they had a higher risk of cancer when compared to their normal weighted peers. In addition, they found that even when they took into account the diet and fitness levels of their obese participants, the risk remained high for people in stage 3.

So, how is this possible? How are SOME obese people able to maintain normal or near optimal health levels?  The present study does indicate that the obese individuals in stage 1 were more fit than the others. It is also entirely possible that the healthy obese individuals were consuming more fruits and vegetables, were getting 8 hours of sleep, drinking their 8 glasses of water and coping better with life stress. It is possible that these individuals had “healthier” lifestyles than their obese peers and therefore successfully reduced their risk for many chronic conditions.

TAKE HOME MESSAGE: If you are obese make sure you understand what your risk is before setting off on a stressful weight loss program. It is important to realize that weight loss does not necessarily mean improved health. Stop focusing on the scale and re-focus on your overall lifestyle. This will reduce your risk for several chronic diseases and in time (perhaps more time than you hoped) you will lose weight!

And remember, you have control of your HALF!