Aerobic exercise like jogging, biking, swimming or mountaineering is a fundamental strategy to maintain cardiovascular and overall health. The intensity of aerobic exercise is significant to find out how much time it’s best to spend training with a purpose to reap its advantages.
As an exercise science researcherI support the American College of Sports Medicine’s suggestion of a minimum of 150 minutes per week of moderate aerobic exercise, or 75 minutes per week of high-intensity exercise. But what does exercise intensity mean?
There is a linear relationship between heart rate and exercise intensity, meaning because the exercise intensity increases, so does heart rate. Heart rate zone training, which uses heart rate as a measure of exercise intensity, has increased in popularity latelypartially resulting from the ubiquity of wearable heart rate technology.
The way exercise intensity is often described is problematic because one person’s “vigorous” could also be one other’s “moderate.” Heart rate zone training tries to supply an objective measure of intensity by breaking it down into various zones. But heart rate can be influenced by temperature, medications and stress levelswhich can affect readings during exercise.
Heart rate and exercise intensity
The gold standard for determining aerobic exercise intensity is to measure the quantity of oxygen consumed and carbon dioxide exhaled. However, this method is cumbersome since it requires people to wear a respiration mask to capture respiratory gases.
An easier way is to predict the person’s maximum heart rate. This will be done with an equation that subtracts the person’s age from 220. Although there’s controversy surrounding the perfect strategy to calculate maximum heart rate, researchers suggest this method remains to be valid.
The American College of Sports Medicine outlines five heart rate zones based on an individual’s predicted heart rate maximum. Zone 1, or very light intensity, equals lower than 57% of maximum heart rate; zone 2, or light intensity, is 57% to 63%; zone 3, or moderate intensity, is 64% to 76%; zone 4, or vigorous intensity, is 77% to 95%; and zone 5, or near-maximal intensity, is 96% to 100%.
However, other organizations have their very own measures of exercise intensity, with various ranges and descriptions. For example, Orange Theory describes their zone 2 training as 61% to 70% of maximum heart rate. Complicating matters even further, corporations that produce heart rate monitors even have higher thresholds for every zone. For example, Polar’s zone 2 is as much as 70% of maximum heart rate, while the American College of Sports Medicine recommends a zone 2 of as much as 63%.
Adapting heart rate zones
Zone training relies on the concept that how the body responds to exercise is a minimum of partially determined by exercise intensity. These adaptations include increased oxygen consumptionessential cellular adaptations and improved exercise performance.
Zone 2 has received plenty of attention from the fitness community due to its possible advantages. Performance coaches describe zone 2 as “light cardio,” where the intensity is low and the body relies mainly on fat to fulfill energy demands. Fats provide more energy in comparison with carbohydrates, but deliver it to cells more slowly.
Because fat is more abundant than carbohydrates within the body, the body responds to the cellular stress that exercise causes in muscle cells by increasing the variety of mitochondriaor the energy-producing component of cells. By increasing the variety of mitochondria, the body may develop into higher at burning fat.
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On the opposite end of the spectrum of exercise intensity is high-intensity interval training, or HIIT. These workouts involve exercising at a high intensity for brief durations, like an all-out sprint or cycle for 30 seconds to a minute, followed by a period of low intensity activity. This is repeated six to 10 times.
During this type of high-intensity activity, the body primarily uses carbohydrates as a fuel source. During high-intensity exercise, the body preferentially uses carbohydrates since the energy demand is high and carbohydrates provide energy twice as fast as fats.
Some individuals who turn to exercise to lose fat may eschew high-intensity training for zone 2, because it’s considered the “the fat burning zone.” This could also be a misnomer.
Researchers have found that high-intensity interval training produces an analogous increase in markers for mitochondria production in comparison to longer, moderate aerobic training. Studies have also shown that high-intensity exercisers construct muscle and improve insulin resistance and cardiovascular health much like moderate-intensity exercisers, and so they made these gains faster. The essential trade-off was discomfort during bouts of high-intensity exercise.
Moderate- or high-intensity exercise?
With various guidelines around heart rate zones and conflicting evidence on the potential advantages of coaching in each zone, exercisers could also be left wondering what to do.
In order to yield the health advantages of exercise, the most significant variable to contemplate is adhering to an exercise routine, no matter intensity. Because the body adapts in similar ways to moderate- and high-intensity exercise, people can select which intensity they like best or dislike the least.
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Notice that the American College of Sports Medicine’s suggestion for exercise falls under moderate intensity. This is similar to zone 3, or 64% to 76% of maximum heart rate, a spread you possibly can only meet within the upper levels of most zone 2 workouts. If you’re not seeing desired results together with your zone 2 workouts, try increasing your intensity to achieve the moderate level.
A commonly reported reason for not exercising is a lack of time. For people short on time, high-intensity training is a very good alternative to steady-state cardiovascular exercise. For individuals who find exercising at such a high intensity uncomfortable, they will get the identical profit by doing moderate-intensity exercise for an extended period.