Several factors affect your heart rate during exercise, including your age, level of fitness and rate of exertion. But you may overlook the role your body position can play in determining your heart rate during and directly following a workout. Supine positions appear to reduce your heart rate when compared to erect positions during exercise, suggesting that your heart has to work harder when your lower body is more vertical than horizontal relative to your upper body.
Heart Rate During Exercise
Generally speaking, there aren't a ton of exercises you can do with a horizontal body position that qualify as aerobic. Many resistance exercises, such as pushups and planks, can increase your heart rate sharply, but this has more to do with the intense muscle contractions than your body position. A 1989 study in the journal "Medicine and Science in Sports and Exercise" found that recumbent, or horizontal, bikes resulted in less cardiovascular effort than standard bikes; however, a 2005 study in the "Archives of Physical Medicine and Rehabilitation" found no such difference in cardio effort relative to body position.
Body position does not appear to have a significant effect on your heart rate during exercise so much as exercise intensity, according to a 2004 study published in the "Journal of Exercise Physiology." Researchers found that heart rate did not change significantly relative to body position during a series of resistance exercises, but higher-intensity exercises such as the hack squat resulted in spikes in the heart rate.
Heart Rate Recovery
Although your body position doesn't appear to have a significant impact on your heart rate during a workout, it does have a measurable impact directly following one. A 2006 study sponsored by the American Heart Association found that heart rate recovery was significantly higher among subjects in the standing position than in the sitting or supine positions. Researchers concluded that this change in heart rate recovery could be due to changes in blood pressure and stroke volume, suggesting that you will recover from a workout faster when sitting or lying down.
A 2003 study published in the "Chinese Journal of Physiology" found that resting heart rates were significantly higher in subjects in the standing position when compared to those in the supine or sitting positions. Interestingly, the study also found that heart rates jumped considerably during changes in body position, from sitting to standing or standing to sitting. Workouts involving frequent changes in body position may affect heart rate more than exercises involving consistent body posture.
- MSN Healthy Living: Bike Dilemma -- Regular or Recumbent?
- Journal of Exercise Physiology: The Effects of Exercise Intensity and Body Position on Cardiovascular Variables During Resistance Exercise
- American Heart Association Journals: Abstract 2605 -- Effect of Body Position on Heart Rate Recovery
- Chinese Journal of Physiology: Changes in Heart Rate and R-Wave Amplitude With Posture
Steven Kelliher is an experienced sports writer, technical writer, proofreader and editor based out of the Greater Boston Area. His main area of expertise is in combat sports, as he is a lifelong competitor and active voice in the industry. His interviews with some of the sport's biggest names have appeared on large industry sites such as ESPN.com, as well as his own personal blog.