Exercise to increase endurance

Course objectives, Control of Human Movement 2

Reading for Control of Human Movement 2:

sections on "exercise Prescription for cardiorespiratory fitness" from:

American College of Sports Medicine. (1998). American College of Sports Medicine Position Stand. The recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults. Medicine & Science in Sports & Exercise, 30, 975-91.

Full text versions of this article are available through the University's Medline account on OVID (unique identifier 98287757) or by accessing the list of position stands listed at the ACSM web site.

---

Prescription parameters

Exercise prescriptions specify values for three parameters: intensity, duration, and frequency. The parameters contribute to a total exercise stimulus called training volume

Specific prescription parameters to enhance endurance (American College of Sports Medicine, 1998b).

1. Frequency of training: 3 to 5 days a week

2. Intensity of training: 50%-85% of maximum oxygen uptake reserve (VO2R)

   Therapists can calibrate exercise intensity by establishing a training heart rate at:

   • 65%-90% of maximum heart rate (HRmax)
   • or 50%-85% of HRmax reserve (HRR).

   Lower intensity exercise

   • 55-64% of HRmax
   • 40-49% of V·O2R or HRR

   is appropriate for unfit individuals.

   Duration of training: 20-60 min of continuous or intermittent activity, depending on intensity

   • Lower-intensity exercise should be performed for at least 30 minutes

   • More intense exercise should last at least 20 minutes

   • Less fit individuals can "accumulate" exercise bouts throughout the day as long as each bout lasts at least 10 minutes.

   • Individuals will more readily attain "total fitness" with exercise sessions of moderate intensity and longer duration. Moderate intensity exercise is safer and associated with better adherence than more intense programs.

   Mode of activity:

   • large muscle groups
   • continuous,
   • rhythmical and aerobic

   examples include: walking-hiking, running-jogging, cycling-bicycling, cross-country skiing, aerobic dance/group exercise, rope skipping, rowing, stair climbing, swimming, skating.

   "The most effective exercise prescription begins with a type of aerobic activity the patient enjoys. A prescribed schedule of stepwise increments in frequency, duration, and intensity gradually leads to a maintenance level of fitness (Kligman & Pepin, 1992, p. 33)."

---

Special groups

People with hypertension (ACSM, 1993)

• HTN (140/90 mm Hg) in 17 percent of Americans
• independent risk factors: male sex, black race, age, family history
• standard prescription parameters apply
• primary prevention strategy: endurance exercise reduces the rise in BP that occurs over time in people at risk
• tertiary prevention:
  • endurance exercise produces 10 mm reductions, on average, in systolic and diastolic BP in people with mild (140-180/90-105) essential hypertension.
  • greater reductions in people with HTN secondary to renal dysfunction
  • active, fit individuals with HTN have lower mortality than those with HTN who are sedentary and unfit.

People with type 2 (adult onset) diabetes mellitus (Albright et al., 2000)

• Endurance exercise decreases blood glucose levels and improves insulin sensitivity for up to 72 hours.
• Autonomic neuropathy affects HR response to exercise: rather than HR, rating of perceived exertion (RPE) is a safe guide to exercise intensity. RPE of 10 - 12 is recommended.
• Sensory neuropathy may preclude a walking program and necessitate non-weight-bearing exercise.
• Therapists must consider a person's readiness to change lifestyle and modify their intervention according to the stages of change.

Rehabilitation, including aerobic and resistance exercise, for people with neuromuscular diseases, from the Muscular Dystrophy Association (MDA) web site.

---

Training heart rate (THR)

Resting heart rate (RHR)	training heart rate (THR)	maximum heart rate (MHR) MHR=220-age in years
HRmax reserve (HRR) = MHR-RHR

THR is determined using some version of the Karvonen Formula (Karvonen, Kentala, & Mustala, 1957):

1. THR=a percentage of MHR

   (0.70) x (220-60) = 112

2. THR=RHR plus a percentage of the HRR

   80 + (0.70) x [(220-60)-80] = 136

While the first equation is easy to teach to patients, applying it to older people can be problematic. In older people, the equation may calculate a THR that is close to the RHR, and imply that the person may exercise at only the most trivial intensities. In these cases, therapists should use the second formula, or have the person judge intensity through a "rating of perceived exertion" (PRE).

---

Rating of perceived exertion (RPE) (Dishman, 1994)

How does your exercising "feel" to you?	Rating Scale
Very, very light	6 - 8
Very light	9 - 10
Fairly light	11 - 12
Somewhat hard	13 - 14
Hard	15 - 16
Very	17 - 18
Very, very hard	19 - 20

HR and RPE are surrogate measures that help therapists estimate exercise intensity as a percentage of VO₂max or of VO₂ reserve. We assume that HR and RPE relate linearly to VO₂. The table below (U.S. Department of Health and Human Services, 1996, Table 2-4, p.33) illustrates the relationship in detail.

---

Benefits of endurance training (Kligman & Pepin, 1992; American College of Sports Medicine, 1998a).

• maintain and improve cardiovascular function, maximal VO2, cardiac output, and arteriovenous O2 difference

• reduce risk factors associated with coronary artery disease, diabetes mellitus, hypertension, obesity, hyperlipidemia, and constipation

• improve health status and increase life expectancy.

• Improve bone health and reduce risk for osteoporosis, especially in postmenopausal woman (Nelson, Dilmanian, Dallal, & Evans, 1991; Gutin & Kasper, 1992)

• improve postural stability and reduce risk of falling and associated injuries and fractures

• preserve cognitive function, alleviate symptoms of depression, and improve concepts of personal control and self-efficacy.

---

References:

Albright, A., Franz, M., Hornsby, G., Kriska, A., Marrero, D., Ullrich, I., & Verity, L.S. (2000). American College of Sports Medicine position stand. Exercise and type 2 diabetes. Medicine & Science in Sports and Exercise, 32, 1345-60. full text version is available through the list of position stands at the ACSM web site.

American College of Sports Medicine. (1993). American College of Sports Medicine position stand. Physical activity, physical fitness, and hypertension. Medical Science in Sports and Exercise, 25,10, i-x.

full text version is available through the list of position stands at the ACSM web site.

American College of Sports Medicine. (1998a). American College of Sports Medicine position stand. Exercise and physical activity for older adults. Medical Science in Sports and Exercise, 30, 992-1008.

full text version is available on Medline, Unique Identifier 98287758, or through list of position stands at the ACSM web site.

American College of Sports Medicine. (1998b). American College of Sports Medicine Position Stand. The recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults. Medicine and Science in Sports and Exercise, 30, 975-91.

full text version is available on Medline, Unique Identifier 98287757, or through list of position stands at the ACSM web site.

Dishman, R.K. (1994). Prescribing exercise intensity for healthy adults using perceived exertion. Medicine & Science in Sports & Exercise, 26, 1087-94.

Gutin, B. and Kasper, M.J. (1992). Can vigorous exercise play a role in osteoporosis prevention? A review. Osteoporosis International, 2, 55-69.

Hillegass, E.A., & Sadowsky, H.S. (1994). Essentials of cardiopulmonary physical therapy. Philadelphia: W.B. Saunders.

Karvonen, M., Kentala, K., & Mustala, O. (1957). The effects of training heart rate: A longitudinal study. Annals of Medicine and Experimental Biology Fenn 35, 307-315.

Kligman, E.W., & Pepin, E. (1992). Prescribing physical activity for older patients. Geriatrics, 47(8), 33-4, 37-44, 47.

McArdle, W.D., Katch, F.I., & Katch, V.L. (1996). Exercise physiology: Energy, nutrition, and human performance. Baltimore: Williams and Wilkins.

Nelson, M. E., Dilmanian, F.A., Dallal, G.E., & Evans, W.J. (1991). A one-year walking program and increased dietary calcium in postmenopausal women: Effects on bone. American Journal of Clinical Nutrition, 53, 1304-1311.

U.S. Department of Health and Human Services. (1996). Physical activity and health: A Report of the Surgeon General. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Preventtion, National Center for Chronic Disease Prevention and Health Promotion.

The chapter of the report that includes Table 2-4 is available in .pdf format at http://www.cdc.gov/nccdphp/sgr/pdf/chap2.pdf

---

Last updated 4-47-01 ©Dave Thompson PT
return to PHTH 7243 / OCTH 7242 lecture schedule