How much physical exercise do you need to live a long and

healthy life?

How many sessions per week? [frequency]

How long per session? [duration]

How hard should you go? [intensity]

Drangsholt 2015

What type of scientific studies are available to answer these

questions?

Cohort studies - healthy people have baseline measurements and then are followed over time until

they die.

People that don’t exercise (at baseline) are compared to those

that exercise to various degrees.

Study 1

Taiwanese Study 1 - Methods

• Cohort study of 416,000 people in a medical screening program in Taiwan from 1996 to 2008

• Average followup time was 8 years

• Self-adminstered baseline questionnare about leisure time physical activity

• Followup with National Death index in Taiwan and cause of death

Self-reported measures of physical activity were used

These reports were converted into Met-hours of activity

BORG SCALE OF PERCEIVED EXERTION

Physical activity MET

Light intensity activities < 3sleeping 0.9watching television 1.0writing, desk work, typing 1.8

walking, 1.7 mph (2.7 km/h), level ground, strolling, very slow 2.3

walking, 2.5 mph (4 km/h) 2.9Moderate intensity activities 3 to 6

bicycling, stationary, 50 watts, very light effort 3.0

walking 3.0 mph (4.8 km/h) 3.3

calisthenics, home exercise, light or moderate effort, general 3.5

walking 3.4 mph (5.5 km/h) 3.6

bicycling, <10 mph (16 km/h), leisure, to work or for pleasure 4.0

bicycling, stationary, 100 watts, light effort 5.5

sexual activity 5.8[10]

Vigorous intensity activities > 6jogging, general 7.0

calisthenics (e.g. pushups, situps, pullups,jumping jacks), heavy, vigorous effort 8.0

running jogging, in place 8.0rope jumping 10.0

MET =

Metabolic Equivalents=Multiples of resting Metabolic rate

Drangsholt “Met” examples2 11 2015 Mark Perceived

kcalKcal/ base kcal MTD Exertion

  base rate met kcal per hr event heart rate Borg

Highest level 80 17 1360last min of treadmill test - Bruce Protocol 180's 20

80 15 1200 19

80 14 1120 recent 12K run 170 to 180 18

80 13 1040 sprint triathlon 150 to 180 17Extremely vigorous 80 12 960 16

80 10 800 15

80 9.5 760 fast cycling 230 watts 156 to 171 14

high vigorous 80 8.5 680     13

80 7.5 600 Easy Running 10 min mile 110 to 120 12

mod-vigorous 80 6.5 520     11

80 5.5 440 10

moderate 80 4.5 360 9

  80 3.5 280 90 watt cycling easy 90's 8

light 80 2.5 200 7

  80 1.5 120     7

sedentary 80 1 80 resting in chair 50 to 55 6

  80 0.9 72 sleep 45 to 50 6

MTD Usual planned workout activity is vigorous MET>6.5

MTD Usual specific workout weekly volume is 120 min (2 hr) to 240 min (4 hr) up to 300 (5+ hr) min. in Summer.

MTD Usual unplanned physical activity is fast walking - moderate MET = 3 to 5

High volume + vigorous have highest reductions in mortality

• Circled numbers indicate the lowest hazard ratio or biggest reduction in mortality

• A hazard ratio of 0.50 means 50% reduction in risk of death – 2 times lower than the comparison group

• A hazard ratio of 0.20 means 80% reduction – 5 times lower risk

Over 500 min, outcomes worse For stroke and ischemic heart disease

Figure 2 Daily physical activity duration and all-cause mortality reduction

Chi Pang Wen , Jackson Pui Man Wai , Min Kuang Tsai , Yi Chen Yang , Ting Yuan David Cheng , Meng-Chih Lee , Hui T...

Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study

The Lancet Volume 378, Issue 9798 2011 1244 - 1253

http://dx.doi.org/10.1016/S0140-6736(11)60749-6

30 to 45 min/day vigorous exercise is the sweet (sweat) spot!

0.50 to 0.75 x 6 = 3.5 to 5 hours per week

6.5+ met

~3 to 6.4 met

Figure 1 Relation between physical activity volume and mortality reduction compared with individuals in the inactive group Bars show 95% CIs.

Chi Pang Wen , Jackson Pui Man Wai , Min Kuang Tsai , Yi Chen Yang , Ting Yuan David Cheng , Meng-Chih Lee , Hui T...

Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study

The Lancet Volume 378, Issue 9798 2011 1244 - 1253

Study1 - Summary 1• In general, exercise has huge benefits on

decreasing mortality – better than almost any other behavior or drug therapy.

• Exercise helps reduce death from all diseases studied including cancer.

• The intensity, duration and frequency of exercise makes a difference in the amount of risk reduction.

• Exercise volumes past 5 to 6 hours a week may not add any additional risk reduction esp. for ischemic heart disease.

Study 1 - Summary 2• Ischemic Heart disease shows u-shaped

curve – that is, sweet spot with moderate volume + high intensity. Increasing duration past 300 min/week shows less protection.

• Stroke also shows u-shaped curve – sweet spot is vigorous with medium volume.

• Diabetes helped the most by highest volume – more than any other outcome.

Study 1 - Summary 3 • High (245 min – 4 hr/week) vs. very high

volume (442 min – 6+ hr/week) differences are not different (significant) in terms of reducing mortality.

• Large advantage of vigorous vs. moderate activity level shown in Figure– Any activity above 6 to 8 mets per hour or more

(e.g. Moderate speed of running, moderate speed of cycling.) Walking does not allow people to get to vigorous level (usually).

Study 1 Conclusions• Consistent, modest exercise duration and

frequency appears to be most important in reducing mortality from all causes.

• Second most important factor is intensity level – attaining vigorous activity level vs. moderate activity gives additional health benefits.

Study 2

Men show greater risk reduction fromIncreased intensity of exercise compared to Women

7.5 to 15 met-hr per weekOf vigorous is optimalIn men

7.5 met/ hr x 1 hr Not much gain above 30 met hr

Mortality vs. Physical Activity 23 to 40 met-hr

40 to 74 met-hr

Staying below 75 met-hr per week is likely prudent

=7.5met per hr x 10 hours

e.g. easy running - 6 miles per hr for 10 hours per week

e.g. cycling at ~[200] watts for 10 hours per week

• Ironman athletes are likely at 20 hours x 7 mets per hour or 140 met-hrs per week.

• No mortality data available for this high duration and high intensity activity – too few people in population

• Data exist of small groups of competitive ageing athletes showing heart damage (myocardial scarring) in some long-term marathon runners over age 50.

Optimal zone is 15 to 30 met-hr per week

7.5met per hr x 5 hours

e.g. running 7 min mile (10 met hr) for 3 hours per week

Cycling at ~[200] watts for 5 hours per week

Date of download: 4/16/2015Copyright © 2015 American Medical

Association. All rights reserved.

From: Leisure Time Physical Activity and Mortality:  A Detailed Pooled Analysis of the Dose-Response Relationship

JAMA Intern Med. Published online April 06, 2015. doi:10.1001/jamainternmed.2015.0533

Figure Legend:

Imprecise evidence of Elevated risk of dying from increased exercise – 10x higher than min recommended

Study 3 – JAMA author conclusions:

Our findings on the shape of the physical activity–mortality dose-response curve offer 3 unique and important contributions to inform health care professionals and future guidelines: (1)the currently recommended amounts of LTPA provide most of the longevity benefits, (2)the longevity benefit threshold appears to be approximately 3 to 5 times the recommended physical activity minimum, and (3)there does not appear to be an elevated mortality risk with LTPA levels as high as 10 or more times the recommended minimum.

Examples of activities to achieve these categories are specified in eTable 6 in the Supplement. In our study population, both moderate- and vigorous-intensity activities were associated with longevity benefit.

Study 2No increased risk from high

exercise, but data hint at more risk from increased exercise

over moderate levels

Bottom line for triathletes• Ideal race length is likely sprint or olympic

distance – training about 5 hours per week maximum – to increase longevity

• Most triathletes at half or full ironman distances are far, far above these levels

• Although inadequate information exists, there is accumulating evidence of physical harm from such high duration, high intensity and frequency of exercise in long distance triathletes

Personalized Wellness

• All of these studies are averages of groups of people.

• There is a variable response to physical exercise and morbidity, mortality

• The key to personalized optimal health and wellness is to track your own biomarkers under various conditions to find what is optimal for you using intermediate biomarkers as a guide.

Other hazards of training greater than ~10 hours per

week• Over-training • Overuse injuries• Psychological burnout • Negative impact of long training on work,

family life• Depletion of critical biomarkers such as iron,

ferritin, white blood cells, others.• Immunocompromise (greater number of

colds, more prone to Flu) can occur.

Extra Method slides

Multisport advantage over single sport training

• Allows for resting of body and muscles in one area while using other parts the next day workout

• More specifically, allows for supercompensation curves that complement each other – one curve for swimming muscles, one for cycling, one for running

• Cross-train can elevate all sport fitness

• Less boring, more fun

Date of download: 4/16/2015Copyright © 2015 American Medical

Association. All rights reserved.

From: Leisure Time Physical Activity and Mortality:  A Detailed Pooled Analysis of the Dose-Response Relationship

JAMA Intern Med. Published online April 06, 2015. doi:10.1001/jamainternmed.2015.0533

Descriptive Characteristics of 661 137 Study Participants

Table Title:

Extra notes

• Old US recommendation – 30 min per day, 210 (3.5 hr) min per week.

• New US recommendation – 60 min per day, 420 min (7 hr) per week.

• Activity monitors like Fitbits will likely revolutionize research in this area – move from self-reported to sensor-based studies – and remove the problems with over-reporting of activity.

Multivariate Relative Risk of Cardiovascular Disease and Relative Risk Adjusted for Age and Walking Time, According to Walking Pace.

Manson JE et al. N Engl J Med 2002;347:716-725.

NEJM 2002

• CONCLUSIONS

• These prospective data indicate that both walking and vigorous exercise are associated with substantial reductions in the incidence of cardiovascular events among postmenopausal women, irrespective of race or ethnic group, age, and body-mass index. Prolonged sitting predicts increased cardiovascular risk.