Evidence has shown the multiple benefits of physical activity, including lowering the risk of heart disease, stroke, Type 2 diabetes mellitus and even certain cancers like colon and breast cancers. Local physical activity guidelines advocate partaking in a minimum of 150 minutes a week of moderate-intensity aerobic activity per week, or 75 minutes a week of vigorous-intensity aerobic activity, or a mix of the two, whereby 2 minutes of moderate-intensity aerobic activity is equivalent to 1 minute of vigorous-intensity aerobic activity. Guidelines also advise general strengthening exercises for major muscle groups at least a minimum of 2 times a week.
Due to work, availability of exercise partners, and various other reasons, some might opt to do all their physical activity during the weekend. People who exercise only one or two days a week, but meet the physical activity guidelines, are known as ‘weekend warriors’.
However, there may be some concerns regarding this pattern of activity. Dr Ivy Lim, consultant sports physician, Changi General Hospital, shares the common injuries, benefits of regular exercise and tips on reducing the potential risks of exercising too much too quickly.
Are weekend warriors more likely to get injured?
Generally speaking, many of the injuries that occur in weekend warriors are a result of relative overload, whereby the body is put through activities that it is not used to. Common injuries include shoulder rotator cuff muscle and tendon injuries, tennis or golfer’s elbow, hamstring muscle and tendon injuries, Achilles tendon (calf muscle tendon injuries), runner’s knee, jumper’s knee, symptomatic knee degenerative arthritis, ankle sprains and plantar fasciitis.
Weekend warriors who are otherwise inactive during the rest of the week may be prone to incurring such injuries. These injuries may also occur in those who exercise more regularly, but start on a new type of activity too fast or too soon, or increased the volume or intensity of their exercise too rapidly.
Many of these overuse injuries tend to improve with rest, but will recur when the same activity is resumed. Often, these injuries require further treatment, for example, physiotherapy for specific stretching, strengthening or control exercises, shockwave therapy or injections. However, weekend warriors may unknowingly ignore the symptoms of these injuries as they treat it as part and parcel of their sports or exercises, especially if the aches and pains do not affect them much for the rest of the week. This may lead to recurring injuries.
For those who experience symptoms such as pain, joint swelling or stiffness after their weekend activities, it is advisable for them to seek further medical attention. Further therapies are often needed to prevent the recurrence of these injuries.
Is exercising one to two days a week less beneficial to health than exercising more regularly throughout the week?
A study published in the JAMA Internal Medicine journal found that exercising one to two days a week may be sufficient to reduce the risk of death from all causes, cardiovascular disease or cancer. Compared with inactive study participants, those in the ‘weekend warrior’ category had a 30% lower risk of dying from all causes, 40% lower risk of dying from cardiovascular disease, and 18% risk of dying from cancer.
However, data from the same study population suggests that there is an association between the amount of moderate- to vigorous-intensity physical activity done and cardiovascular risk factors such as high-density lipoprotein (‘good cholesterol’), systolic blood pressure and HbA1c (an indication of the blood sugar control in one with diabetes mellitus). Those in the study who were regularly active had the most favourable risk factor profiles, while those who were classified as weekend warriors had intermediate levels of risk factors. Hence, for someone with cardiovascular risk factors such as high blood pressure or diabetes mellitus, it may be more beneficial to do physical activity more regularly throughout the week.
In addition, those with certain chronic medical conditions such as high blood pressure or diabetes mellitus may benefit from some acute but short-term effects of physical activity. For example, moderate intensity physical activity results in an acute drop of blood pressure, with this effect lasting for around 22 hours.
Those with hypertension may want to do moderate-intensity physical activity on a daily basis to ride on this effect, i.e. using physical activity as ‘medicine’ to aid in the control of their condition.
Similarly, for those with diabetes mellitus, a decrease in blood glucose levels has been observed in diabetics following mild- and moderate-intensity exercise, with the effect lasting for 2 to 72 hours after the exercise bout. Those with diabetes mellitus or on certain diabetes medications such as secretagogues (e.g. glipizide) or insulin injections should also try to exercise regularly to allow for better adjustment of their medication dosage and timings. It is important that they inform their doctors of their exercise regime, so as to allow for more optimal monitoring of their condition, medications, and the effect of physical activity on their disease control.
Is it safe to do the recommended physical activity within one to two days?
There have been cases of apparently healthy persons dying during physical activity. Indeed, there is a paradoxical increase in the risk of heart attack or sudden cardiac death during or shortly after exercise, particularly if the exercise is of vigorous intensity. However, this is more likely to occur in adults with some form of structural heart disease. For healthy people, the relative risk of suffering a heart attack during exercise decreases with increasing physical activity.
A study analysing victims of exertion-related deaths found that more than half occurred during unaccustomed exertion while 16% occurred during habitual exercise. Another study
analysing sufferers of heart attacks found that it is not common for heart attacks to occur during vigorous-intensity physical activity, with only 4.4 percent of them reporting heavy exertion equivalent to that of vigorous-intensity physical activity within one hour before the onset of a heart attack. The risk of suffering a heart attack during vigorous-intensity physical activity also appears to be less in those who undergo regular vigorous-intensity physical activity.
For those who suffered a heart attack, the risk that this occurred in the hour after vigorous intensity physical activity is 107 times higher than the risk of suffering a heart attack during less vigorous physical exertion or none for those who exerted themselves less than once a week. Those who exerted themselves at least 5 times a week had a relative risk of suffering a heart attack of 2.4.
Putting all the above together, it is possible that weekend warriors who are otherwise sedentary the rest of the week, and exert themselves with unaccustomed activity, may be at risk of sustaining a heart attack or sudden cardiac death. The solution is not to reduce physical activity, as sedentary behaviour on its own is associated with a higher risk of death.
Following a few simple rules can reduce the risk of suffering a cardiac event related to exercise.
- Start low and go slow in terms of physical activity, and slowly progress the intensity of physical activity.
- Do not exercise during periods of acute systemic illness, like fever or myalgia (generalised body aches). Studies have also shown that prior early warning symptoms were present in a number of persons who have suffered sudden cardiac arrest during sporting activities, thus if symptoms such as palpitations, fainting spells or seizures or dizziness, chest pain or unexplained breathlessness, or extreme fatigue during exercise or sports are present, one should see a doctor as soon as possible to evaluate these.
- Doing a self-administered pre-participation screening questionnaire such as PAR-Q+ or the Get Active Questionnaire can highlight possible potential issues that may require evaluation or clearance by one’s doctor prior to starting physical activity. Doing regular screening for cardiovascular risk factors such as diabetes mellitus, high blood pressure and high cholesterol levels, and controlling them if present, will also help to reduce the risk of cardiac issues due to exercise. However, screening has its limitations and may not pick up every single condition, and the individual’s condition may change as well. As such, one should always seek medical attention for further evaluation if there are concerns.
In summary, being a weekend warrior is not necessarily a bad thing, though one must be cautious not to be a weekend warrior who overexerts too quickly and is otherwise sedentary the rest of the week, as that can increase the risk of injuries or even sustaining cardiac events related to physical exertion.