Do the Splits:Can Patients Divide the Daily Workout?

Taryn Smith, PAS-3Faculty Mentor: Daniel O’Donoghue, PA-C, PhD

OU Health Science CenterOklahoma City, OK

Why Address Exercise?Pts resistant to providers’ advice on

matterToo little timeFeel inadequate or fear injuryVague idea of benefitsLack of motivation

What kills Americans?

Heart Disease33%

Cancer31%

Chronic Lower Respiratory

Disease7%

CVA7%

Accidents6%

Alzheimer's 4%Diabetes

4%

Flu/Pneumonia

3%Kidney Dz

3%Suicide

2%

What kills Americans?

Heart Disease33%

Cancer31%

Chronic Lower Respiratory

Disease7%

CVA7%

Accidental in-jury6%

Alzheimer's 4%

Diabetes4%

Flu/Pneumonia

3%Kidney Dz

3%Suicide

2%

Why Exercise?Improved moodRestful sleepGreater strengthPreserved learning/JudgmentLonger lifePhysical appearance

WeightBlood pressureStress & DepressionRates of CVD, malignancy, CVA, DMFall risk/hip fractures

Clinical QuestionIn adults with no history of coronary artery disease (CAD), is a summative 30 minutes of daily aerobic activity as effective at minimizing risk factors for CAD as a consecutive 30 minutes of daily aerobic activity?

Objectives•Consider why patients may desire an

alternative to “traditional” exercise•Define what constitutes a short-bout

workout•Evaluate the tangible benefits linked to

short-bout workouts•Examine the validity of the findings•Consider literature limitations and

avenues of future research

The Recommendation

2008 Physical Activity Guidelines for Americans

≥ 150 minutes/weekModerate intensity

•Anything less than the traditional 30+ minutes▫10, 15, 20, 30 minutes

Define Short-Bout Exercise

The Studies

Jakicic et al, 1995• N = 48• Obese women• 25 to 50 yoaSubjects• Any type of exercise; monitored by TriTrac

accelerometers• Increasing workout duration: 203040 min• 5 days/wk x 20 weeks• SB: 10 min intervals• LB: all at once

Specifics• SB> LB exercise adherence• SB = LB weight loss• SB = LB VO2max improvements• SB: 10 min + 5 min (p = 0.08)

Results

Murphy & Hardman, 1998• N = 34• Sedentary women• 36-53 yoaSubjects• “Brisk walking”• 30 min x 5 days/wk x 10 weeks• SB: 10 min intervals x 3• LB: all at once• Controls

Specifics• SB vs. Controls

• Weight loss• Waist circumference

• SB & LB vs. Controls• Improved VO2max

Results

Jakicic et al, 1999• N = 115• Overweight women• 25 to 45 yoaSubjects• Brisk walking or similar• Increasing workout duration: 203040 min• 5 days/wk x 18 months• SB• SB + home treadmills• LB

Specifics• SB(+) > SB: weight loss• SB (+) = LB: weight loss• All groups: decreased body fat• All groups: improved VO2max

Results

Schmidt et al, 2001• N = 26• Overweight/obese, sedentary

women• College students, 17-23 yoa

Subjects• Stationary cycling• Increasing from 3 5 d/wk x 12 weeks• SB – 10 min intervals x 3• SB – 15 min intervals x 2• LB – 30 min intervals• Controls

Specifics• All exercising groups:

• Weight loss, WC, BMI, skinfold thickness

• Improved VO2max

Results

The Payoff: SB vs. LB Increased workout

adherence

Equivalent weight loss

Similar VO2max increases

Equal reduction of body fat

%

Decreased waist

circumference

Lowered BMI in > 25

cohort

Decreased skinfold

thickness

Trusting the Science

•Designs of studies

•p values

•Varied subgroups within cohort

Literature Limitations

• Small sample sizes

• Self-reported data

• Confounding interventions

• Short study duration

• Decreased exercise over

time

• Older data

Future Research Improvements

•Larger sample sizes

•Different cohorts

•Longer study length

•Improved endpoints

•Eliminate confounders

References• 2008 Physical activity guidelines for Americans. US Department of Health

and Human Services (HHS), Office of Disease Prevention and Health Promotion. Washington: HHS; 2008. (Accessed March 14, 2012, at http://www.health.gov/paguidelines/pdf/paguide.pdf).

• Murphy MH, Hardman AE (1998) Training effects of short and long bouts of brisk walking in sedentary women, Med. Sci. Sports Exerc., 30: 152–15.

• Schmidt WD, Biwer CJ, Kalscheuer LK (2001) Effects of long versus short bout exercise on fitness and weight loss in overweight females, J. Am. Coll. Nutr. 20(5): 494-501.

• Jakicic JM, Wing RR, Butler BA, Robertson RJ (1995) Prescribing exercise in multiple short bouts versus one continuous bout: effects on adherence, cardiorespiratory fitness, and weight loss in overweight women, International Journal of Obesity, 19: 893-901.

• Jakicic JM, Winters C, Lang W, Wing RR (1999) Effects of intermittent exercise and use of home exercise equipment on adherence, weight loss, and fitness in overweight women: a randomized trial, JAMA, 282(16): 1554-1560.

References• Deaths and Mortality. Centers for Disease Control and Prevention

(CDC). Atlanta, GA; March 2012. (Accessed 9/24/12 at http://www.cdc.gov/nchs/fastats/deaths.html).

• Physical Activity and Health: The Benefits of Physical Activity. Centers for Disease Control and Prevention (CDC). Atlanta, GA; February 2011. Accessed 9/24/12 at http://www.cdc.gov/physicalactivity/everyone/health/index.html).

• Physical Activity: Measuring Physical Activity Intensity. Centers for Disease Control and Prevention (CDC), Atlanta, GA. December 2011. Accessed 9/24/12 at http://www.cdc.gov/physicalactivity/everyone/measuring/index.html).