November/December 2022

Exercise and Respiratory Health
By Jennifer Van Pelt, MA
Today’s Geriatric Medicine
Vol. 15 No. 6 P. 18

Getting Physical to Offset Age-Related Decline in Lung Function

According to the American Lung Association, lung function declines with age, even in healthy older adults, as a normal part of the aging process. Age-related respiratory changes include a weakening of the diaphragm muscle, loss of elasticity in lung tissue, and changes in the rib cage bones that affect the ability of the lungs to expand.1 Regular exercise throughout life is important not only for cardiac and muscular function but also for optimal lung health. Although aging-related lung changes still occur, exercising through older age can minimize their effects.

Common clinical measures of respiratory function (see sidebar) naturally decline with aging. Research has shown that aging-related lung function decline can contribute to multimorbidity in older adults by limiting their physical abilities. Multimorbidity—the coexistence of two or more chronic diseases in an individual—increases the likelihood of adverse events (eg, falls, hospitalization) for older adults and is clinically challenging for geriatric professionals to manage. Multimorbidity is present in 65% of those aged 65 to 84 years and in 82% of those 85 years and older.2

Exercise recommendations for older adults generally focus on preventing cardiovascular disease, osteoporosis, and frailty—three common conditions in older age multimorbidity. Exercising with a focus on these will also enhance respiratory functioning; however, adding lung health to exercise goals can help offset aging-related lung changes as well as potentially identify barriers to exercise and reduce adverse effects of multimorbidity.

Research indicates that a variety of physical activities and breathing-focused training activities can help combat aging-related lung decline in more active older adults as well as in those who are frail, sedentary, or have mobility limitations or lung conditions.

In 2016, in a Scientific Statement, the American Heart Association (AHA) recommended that cardiorespiratory fitness (CRF)—measured by VO2 max—be regularly assessed in older adults and considered as another clinical “vital sign.”3 According to the AHA, “CRF reflects the integrated ability to transport oxygen from the atmosphere to the mitochondria to perform physical work.” CRF is a measure of functional capacity and integrated physiological processes that begin with pulmonary ventilation and involve cardiac functioning and efficient blood flow and transport of oxygen to the muscles. A cardiopulmonary exercise test (see sidebar) may be performed in older adults at risk for cardiovascular disease, but clinical attention is typically focused more on the cardiac variables assessed during the exercise stress test, such as hemodynamic and electrocardiographic responses to exercise. The AHA noted that research indicates that CRF is a “more powerful predictor of mortality risk than the traditional risk factors such as hypertension, smoking, obesity, hyperlipidemia, and type 2 diabetes mellitus.”3

Although exercise undoubtedly improves CRF, whether it also can slow aging-related declines in pulmonary function (ie, forced expiratory volume, or FEV1) has been an ongoing debate among researchers and clinicians. Because FEV1 is affected by aging-related loss of lung elasticity and changes in alveolar-capillary membrane, it has long been thought that exercise could not address these aging-related lung changes. However, the results of recent longitudinal studies suggest that regular physical activity can, in fact, improve FEV1.4

In the English Longitudinal Study of Aging, which has regularly followed more than 18,000 adults older than 50 years and documents aging-related changes, improved lung function was associated with being physically active. For the lung health analysis, approximately 3,000 initially healthy adults with a mean age of approximately 63 years had spirometry upon entering the study and at an eight-year follow-up.5 Participants who had reported remaining active or becoming active had significantly better FVC and FEV1 measures. Those who reported remaining inactive had a higher risk of developing poorer lung function over the course of the study.4,5

In this study, the link between lung function and cognitive decline was also evaluated. In approximately 6,000 of the participants who had data available for baseline spirometry and four follow-up visits that evaluated cognitive functioning, participants with lower lung function at baseline than others had a faster rate of developing cognitive impairment, such as memory loss and declines in time orientation and executive functioning.6

Another similar study, the Canadian Longitudinal Study on Aging, also analyzed lung function and physical activity.7 This study followed more than 51,000 adults aged 45 to 85 years to determine the effects of aging on health and quality of life. The lung function study evaluated 20,049 adults with spirometry, physical activity, and sitting time data. Older adults—both healthy and with respiratory diseases—who reported replacing 30 minutes of daily sitting time with any type of physical activity had significantly improved FEV1. The researchers noted that their analysis suggested that sitting for prolonged periods of time causes an acceleration of age-associated physiological decline in lung function and that decreasing sedentary time can improve lung function in older adults. Of note, improvements in lung function occurred with any type of physical activity, not only aerobic activities.5,7

Another analysis of data from this study assessed different types of physical activity and their effects on lung function in approximately 17,000 participants without respiratory disease who had complete data on lung function, physical activity, and sedentary time.8 Physical activities were classified as walking; strengthening; and light-intensity, moderate-intensity, or strenuous physical activity. The researchers found that all types of physical activity were associated with improved FEV1 and FVC in both nonsmoking and smoking adults. Interestingly, strengthening activities in particular were associated with significant improvements in FEV1 and FVC in older smoking adults.8

Exercise Guidance for Older Adults
Aging-related lung changes can decrease exercise performance, though environmental and genetic factors can cause individual differences in how the lung ages. Declining lung function related to aging can contribute to exercise intolerance even in healthy older adults who are regularly physically active. Pulmonary limitations from aging lungs may even occur in older competitive athletes.2 Therefore, any exercise guidance should not only be tailored to the individual’s physical capabilities but also be accompanied by education regarding aging-related lung changes. Some older adults may require supervised pulmonary rehabilitation if they have lung diseases such as COPD or asthma.

There’s a growing paradigm that “exercise is medicine” and should be specifically prescribed—not just a vague recommendation to exercise more but a detailed and individualized prescription for increasing and maintaining regular exercise for the individual patient. The International Conference on Frailty and Sarcopenia Research (ICFSR) published expert consensus guidelines for exercise recommendations for older adults in July 2021.9 Although ICFSR does not specifically address lung health in its guidance, its recommendations do address improving CRF with aging.

Guidelines from the World Health Organization and some US health organizations recommend that adults 65 years of age and older engage in 150 minutes of moderate-intensity or 75 minutes of vigorous aerobic exercise plus at least two days of muscle strengthening exercise per week. Other professional organizations recommend multimodal exercise that includes aerobic, strengthening, balance, and flexibility training. The ICFSR acknowledges that most older adults do not meet the current guideline recommendations for weekly physical activity, and exercise recommendations are not fully integrated into geriatric medical practice.9

The ICFSR notes that exercise amounts recommended by guidelines may be too much for many older adults, especially those who are sedentary, are frail, or have medical conditions that limit mobility.9 It’s now recognized that physical activity below these recommended amounts is also beneficial. Even a small amount of exercise is better than no exercise for older adults, according to the ICFSR. Frail and sedentary older adults may be more able to perform strength training, in particular, since many movements can be done seated or with support when standing. In addition, strength training has been found to improve lung function as well as physical functioning.8,9

Other exercises that may improve lung health and be appropriate for older adults include tai chi and qigong, which involve slow, flowing body movements coordinated with breathing. Both can be adapted to be performed seated if needed. A recent systematic review and meta-analysis found that tai chi/qigong improved FVC and FEV1 as well as did a six-minute walk test performance, a common clinical measure of CRF.10

Respiratory Muscle and Breath Training
For frail and less mobile older adults, as well as those with lung diseases (eg, COPD), methods that focus on strengthening respiratory muscles and deep breathing may also help improve lung health. Respiratory muscle training using breath resistance devices is utilized in supervised pulmonary rehabilitation programs. These devices are available over-the-counter for at-home or unsupervised use once the older adults are trained in their use for breathing exercises. Respiratory muscle training with these devices has been found to improve lung function and respiratory muscle strength, thereby decreasing dyspnea and increasing physical functioning.11-13

Yoga breathing techniques can also improve lung function in older frail adults and can be performed on their own or in combination with gentle chair yoga poses. In one randomized study, 12 weeks of yoga breathing improved respiratory capacity and exercise intolerance in older adults with COPD.14 In another randomized study, yoga breathing improved respiratory muscle strength in institutionalized frail older adults who were unable to perform physical exercise.11 In this comparative study, yoga breathing performed for five days a week for six weeks resulted in greater improvements in respiratory muscle strength than did inspiratory muscle training with a respiratory training device performed for the same duration in another group of frail older adults.11

Another activity to improve lung function that’s appropriate for older adults who have difficulty exercising physically is singing. Because breathing and singing are closely linked physiological processes, singing programs are being investigated to improve respiratory muscle strength in frail older adults and those with COPD. Singing programs for older adults that focus on socialization and musical enjoyment can provide the ancillary benefits of strengthening respiratory muscles and improving lung capacity. Singing programs that specifically focus on improving lung health incorporate vocalization and breathing exercises similar to those used in respiratory therapy, along with singing activities.15 In a pilot study of individuals living in older adult communities, a group singing program held for 75 minutes weekly for 12 weeks improved respiratory muscle function as well as some cognitive functions.16 Research into singing for lung function improvement in older adults and those with lung conditions is ongoing.15

— Jennifer Van Pelt, MA, is a freelance writer and health care researcher located in the Lancaster, Pennsylvania, area.

Clinical Measures of Pulmonary Function

Pulmonary function is generally assessed using spirometry, a diagnostic test that measures lung capacity. It is used to diagnose COPD and asthma, as well as to monitor pulmonary function during and after treatment for lung conditions.

Two spirometric measures include the following:

• Forced vital capacity (FVC), which is the maximum amount of air that can be forcibly exhaled from the lungs after a full inhalation. A normal FVC is approximately 80% of total lung capacity, or 4.8 liters; full lung air capacity is approximately 6 liters, but about 20% remains in the lungs after an exhalation. Due to aging, FVC may decrease by about 0.2 liters per decade after age 35, even in healthy adults who have never smoked.1

• Forced expiratory volume (FEV1), which is the amount of air that can be forcibly exhaled within one second. Due to aging, FEV1 declines 1% to 2% each year after age 25.1

VO2 max, which stands for maximal oxygen uptake or maximal aerobic capacity, is the maximum rate of oxygen consumption as measured during exercise of gradually increasing intensity. VO2 max is assessed during a cardiopulmonary exercise test, or exercise stress test. VO2 max also declines with age, with more accelerated decline occurring after age 40 to 50 years.2

References
1. Lung Capacity and Aging. American Lung Association website. https://www.lung.org/lung-health-diseases/how-lungs-work/lung-capacity-and-aging. Updated November 23, 2021.

2. Roman MA, Rossiter HB, Casaburi R. Exercise, ageing and the lung. Eur Respir J. 2016;48(5):1471-1486.

3. Ross R, Blair SN, Arena R, et al. Importance of assessing cardiorespiratory fitness in clinical practice: a case for fitness as a clinical vital sign: a scientific statement from the American Heart Association. Circulation. 2016;134(24):e653-e699.

4. Burtscher J, Millet GP, Gatterer H, Vonbank K, Burtscher M. Does regular physical activity mitigate the age-associated decline in pulmonary function? Sports Med. 2022;52(5):963-970.

5. O'Donovan G, Hamer M. The association between leisure-time physical activity and lung function in older adults: the English longitudinal study of ageing. Prev Med. 2018;106:145-149.

6. Qiao H, Chen M, Li S, Li Y, Sun Y, Wu Y. Poor lung function accelerates cognitive decline in middle-aged and older adults: evidence from the English Longitudinal Study of Ageing. Arch Gerontol Geriatr. 2020;90:104129.

7. Dogra S, Good J, Gardiner PA, et al. Effects of replacing sitting time with physical activity on lung function: an analysis of the Canadian Longitudinal Study on Aging. Health Rep. 2019;30(3):12-23.

8. Dogra S, Good J, Buman MP, Gardiner PA, Stickland MK, Copeland JL. Movement behaviours are associated with lung function in middle-aged and older adults: a cross-sectional analysis of the Canadian Longitudinal Study on Aging. BMC Public Health. 2018;18(1):818.

9. Izquierdo M, Merchant RA, Morley JE, et al. International exercise recommendations in older adults (ICFSR): expert consensus guidelines. J Nutr Health Aging. 2021;25(7):824-853.

10. Guo C, Xiang G, Xie L, et al. Effects of Tai Chi training on the physical and mental health status in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis. J Thorac Dis. 2020;12(3):504-521.

11. Cebrià i Iranzo Md, Arnall DA, Igual Camacho C, Tomás JM. Effects of inspiratory muscle training and yoga breathing exercises on respiratory muscle function in institutionalized frail older adults: a randomized controlled trial. J Geriatr Phys Ther. 2014;37(2):65-75.

12. Manifield J, Winnard A, Hume E, et al. Inspiratory muscle training for improving inspiratory muscle strength and functional capacity in older adults: a systematic review and meta-analysis. Age Ageing. 2021;50(3):716-724.

13. Vilaça AF, Pedrosa BCS, França ERT, et al. Respiratory muscle training in older adults: review article. Geriatr Gerontol Aging. 2019;13:167-172.

14. Kaminsky DA, Guntupalli KK, Lippmann J, et al. Effect of yoga breathing (Pranayama) on exercise tolerance in patients with chronic obstructive pulmonary disease: a randomized, controlled trial. J Altern Complement Med. 2017;23(9):696-704.

15. Lewis A, Philip KEJ, Lound A, Cave P, Russell J, Hopkinson NS. The physiology of singing and implications for 'Singing for Lung Health' as a therapy for individuals with chronic obstructive pulmonary disease. BMJ Open Respir Res. 2021;8(1):e000996.

16. Fu MC, Belza B, Nguyen H, Logsdon R, Demorest S. Impact of group-singing on older adult health in senior living communities: a pilot study. Arch Gerontol Geriatr. 2018;76:138-146.