“If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would find the safest way to health.”- Hippocrates
Blood pressure (BP) is often a correlated challenge with many chronic problems. Exercise increases oxygen demand in muscles which increases blood flow to skeletal muscles. When participating in high intensity exercise, blood flow can increase 100 times resting pressure. Regular aerobic training (AT) reduces BP in all populations and is recommended as a lifestyle modification for all individuals. Hypertensive individuals are recommended to participate in AT for 30-45 minutes a day to lower BP.
Nocturnal Blood Pressure (BP)
Exercise directly affects nocturnal BP by helping to develop a healthy dip. Dipping, when the blood pressure naturally drops at night, can be a predictor of the likelihood of a cardiovascular event. Generally, aerobic exercise training (ET) reduces BP both during the day and night. There is no evidence that resistance or strength training has any effect on BP. A 10-20% BP dip is considered to be normal. Non-dipping is a risk for hypertension, cardiovascular events, reduced renal function, and increased mortality.
African Americans who commonly do not dip their BP have the highest hypertension rate. AT has a substantial effect on BP by improving dipping in high risk African American populations. After 6 months of regular AT nocturnal BP dipping increased an average of 9.4% in the studied African American population. This is great news because ‘each 5% decrease in nocturnal BP dipping was associated with an 18% increase in the risk of cardiovascular mortality,’ suggesting a reduced dip was detrimental.
‘Isometric exercise training has been found to increase resistance vessel endothelial function and increase training limb artery diameter, blood velocity, and blood flow in concert with reduced vascular conductance.’ (Carlson, 2014)
Isometric training is much less expensive than other resistance exercises and can be done anywhere. It lowers BP in normotensive and hypertensive individuals over time. Lower body isometric training is not commonly prescribed but wall squats can be used as an isometric exercise at different angle intensities to support BP at different rates. Isometric contractions improve resting BP, endothelial function, and provide local vascular adaptations to exercise.
Pregnancy also tends to have challenges on the cardiovascular system. Exercising pregnant women tend to choose walking as their exercise mode. Stretching exercises were found to reduce systolic and diastolic BP in the second trimester and stretching was also found to help control BP in the third trimester. Walking, on the other hand, was not found to be effective at lowering BP in pregnancy. When BP is high during pregnancy it can lead to future metabolic syndrome, stroke, premature birth, low birth weight, gestational hypertension, and preeclampsia. Stretching is a much easier mode of exercise for pregnant women and can be more helpful at lowering BP.
Most exercise is limited by respiratory performance. The American Thoracic Society recommends pulmonary rehabilitation (PR) for exercise intolerant individuals. PR is designed for individuals with reduced lung capacity and other respiratory challenges such as COPD. Exercise helps increase respiratory muscle strength and reduces symptoms of exertional dyspnea in COPD. Individuals with reduced respiratory rate and used PR were more able to perform high intensity exercise to receive the greater physiological benefits and increased respiratory muscle strength.
Different exercise intensities require different volumes of ventilation. Expiration muscles in breathing are faster to tire during exercise than inspiration muscles. Taking shallow, fast breaths takes pressure off of the muscles used for expiration. Strengthening these muscles by forced expiration, expanding the diaphragm and allowing for a higher volume of air to enter the lungs on subsequent inspiration, supports higher lung volume over time. Exercise strengthens breathing muscles and lung strength making breathing easier in respiratory challenged individuals such as the elderly.
Oedema, excessive fluid, accumulates in the interstitial space and must be drained by the lymphatic vasculature. With wound healing, manual lymphatic drainage is very important, especially for women who have just gone through radical mastectomy. Exercises can focus on manual lymphatic drainage and can safely be used freely after mastectomy to support healing. Exercise is the main method of increasing lymphatic flow and drainage. This lymphatic fluid carries proteins, inflammatory mediators, and waste from the interstitial space through the whole body. Skeletal muscle contractions compress lymph vessels to promote flow. With higher intensity exercise, lymphatic circulation allows for more removal of toxins from the body than lower intensity exercise.
Jillian Carnrick, founder and manager of The Dancing Herbalist, has a Masters of Science Degree in Herbal Medicine, practices as a nutritionist, and is a Certified Personal Trainer and Exercise Is Medicine Professional through the American College of Sports Medicine. Join her for live classes and The Dancing Herbalist’s home herbalist courses online for more learning opportunities.