Physical Activity & Breast Cancer

By

Janet Foote, PhD

Discuss the role of movement in:

1. Prevention of breast cancer onset 2. Appropriateness for breast cancer survivors 3. Prevention of Breast Cancer recurrence

Physical ActivityAnaerobic

Aerobic - most prevention/survival research

Bouts up to 2 mins, highest % effort, uses CP & ATP, & results in lactic acid build-up (burning)

Bouts > 2 mins, sub-max effort, uses aerobic processes (O2), w/ training - can sustain for longer periods

Types of Aerobic Activities

walking, jogging, running

cycling

swimming

skiing

household: sweeping, vacuuming etc.

recreational / occupational

Physical Activity & Breast Cancer Risk

Recent comprehensive review - 2007 C M Friedenreich & A E CustBr J Sports Medicine 42:636-647, 2008

1 1.5 2.00.50.25

increased riskreduced risk

50% less likely

17 of 28 cohort studies

Risk

average 20% risk

reduction

Ref: Friedenreich CM & Cust AE, Br J Sports Med 42:636-647, 2008

Any type of Breast Cancer

26 of 34 case-control

studies

average 30% risk

reduction

Ref: Friedenreich CM & Cust AE, Br J Sports Med 42:636-647, 2008

All Types of Breast Cancer

Risk

All studies - 25% reduction in breast cancer risk

Among only those studies finding that activity reduced breast cancer risk

◦ 36% reduction risk in active

Evidence for Aerobic Activity in Prevention of Breast Cancer Onset

Differences by menopausal status

WCRF AICR rating of benefits*:* Premenopausal: “limited suggestive” * Postmenopausal: “probable”

Cohort & Case-control Studies

• WCRF-AICR Food,Nutrition, Physical Activity & the Prevention of Cancer: a Global Perspective,

AICR Washington, DC, 2nd edition 2007.

Breast Cancer Risk: Pre-menopausal

Ref: Friedenreich CM & Cust AE, Br J Sports Med 42:636-647, 2008

Risk

5 signif.

14 n.s.

29 of 31

aver. 40%

Breast Cancer Risk: Post-menopausal

RiskRef: Friedenreich CM & Cust AE, Br J Sports Med 42:636-647, 2008

20 signif.

10 n.s.

30 of 35

aver. 33%

Recreational activityLifetime, activity after age 50 Decreasing categories of BMIAsian, Black, Hispanic (50%, 40%, & 30%)Women with no family historyWomen - ER-/PR- (0.61) vs. ER+/PR+ (0.86)Parous women (28% vs. 22% reduction nulliparous)

Effects were greater for:

Activity Responsive Pathways Immune function

Growth factors, GF binding proteins

Sex hormones & binding proteins

Endogenous antioxidant enzyme systems

Oxidative stress DNA repair

Phase II xenobiotic systemGood review: A. Rundle, Molecular epidemiology of physical activity and cancer, CEBP 14(1):227-236, 2005

Decreased lifetime exposure to estrogen

Decreased % of body fat

Increases immunity & antioxidant defense systems

Intervention Studies

Majority among breast cancer

Significant physiological benefits

Significant psychological benefits

Improved QOL, depression, anxiety

Improved self-esteem

Ref.: DA Galvao & RU Newton, Review of Intervention studies in cancer patients, J Clin Onc 23(4): 899-909, 2005

Intervention Studies

Mostly aerobic activities

Positive effects: resistance training

- anaerobic

Flexibility

Do - able! Benefits!

Activity: Recurrence Prevention Minimize post-treatment weight gain

Maintenance lean body mass (BMD)

Enhance immunity/antioxidant systems

Enhance QOL, fatigue and anxiety

Enhance self-esteem & depression

Advantages: aerobic & resistance tr.

Enhance range of motion flexibility

Getting StartedBring up the subject!

“Here are some things you can do as part of your treatment,…to help you live better and longer”.

Be specific in advice

Provide an exercise prescription

Exercise Prescription Elements1. Frequency - how often

2. Intensity - % effort, 60 - 80%

3. Duration - how long each bout lasts

Initial fitness level

Type of exercise

Additional considerations:

Exercise Prescription: Br CA

Start slowly, but be specific

“3 times during the next week, walk 2 blocks away from your house, turn & walk 2 more blocks & continue until you’ve walked back to your house”

“keep 2 canned goods near your TV & every commercial alternate holding out front, to the side, overhead, curls”

Watching 2 hrs TV nightly:

Physical Activity - Breast Cancer

decreases risk

enhances treatment

improves survival

Beneficial Physical

Activity types

aerobic (cardiovascular)

anaerobic (resistance training)

flexibility (range-of-motion)

Promoting regular activity among:

women at riskwomen undergoing treatmentsurvivors

* Develop own hand-out:check boxes for prescription, diaries

Join: gym w/ set classes (like Curves) program/organization(Bone-builders, Walk Across Arizona, Better Than Ever, litter patrol, dog walkers, Masters Swim club, hiking club, dance classes, etc.)

Enlist: friend, spouse, dog

Pedometer: log steps / day on the calendar working to a 10,000 steps / day goal

Activity Resources

Model it Make it happen