firefit conference 2008 ‘fit for service, fit for the future’ kevin sykes professor of...

Firefit Conference 2008Firefit Conference 2008‘Fit for Service, Fit for the Future’‘Fit for Service, Fit for the Future’

Physiology of Ageing- and possible effects on firefighters

Kevin SykesKevin Sykes Professor of Occupational Health & FitnessProfessor of Occupational Health & Fitness

DirectorCentre for Exercise & Nutrition Science

University of Chester

“So, Mr Jones, how old are you?”

“32?”

If you didn’t know how old you are…….. ….how old would you think you are ?

Many of us are health-conscious

But many still take their health for granted….. … until they lose it!

Prevention is better than cure

We can now expect to live 10 years longer than in the 1950s

1950-2005

Increase in Life Expectancy

20

05

Females live 5yrslonger thanmales

UK Life Expectancy

• Females: Average 82yrsHighest 86yrs Kensington, Chelsea, E.Dorset

Lowest 70yrs Glasgow

• 75% of females will be alive after the age of 75• 50% of males will be alive after the age of 75

• Males: Average 77yrsHighest 81yrs Kensington, Chelsea, E.DorsetLowest 65yrs Glasgow

6

37% CVD

28% Cancer

36% CVD

24% Cancer

Lifespan v ‘Healthspan’

Men Women

Expected Lifespan: 77yrs 82yrs

Expected ‘Healthspan’: 67yrs 72yrs

ADD Life to years… not years to life

100% valuesedentary

Aerobic Fitness & Ageing• Decrease in cardiac function: e.g. HR = 220-Age Cardiac Output Stroke Volume• Decrease in Circulatory capacity: e.g. Increase in peripheral resistance Less blood flow to active muscle• Decrease in muscle O2 uptake: e.g. Reduced a-vO2 diff Reduction in mitochondria & oxidative

enzymes• Reduced Respiratory function (FVC, FEV, RV, MaxVe-1)

VO2Max decreases by 10% per decade after 25-30yrs

HOWEVER……Fit 60yr old fitter than sedentary 20-30yr olds!

• Low aerobic fitness is more important precursor ofall-cause mortality than any of the other risk factors

Aerobic Fitness, Ageing & Longevity

* Least fit x2 as likely to die prematurely from all causes* Reduced lifespan and healthspan

Aerobic Fitness, Ageing & Longevity

Strength & Ageing• Max muscle strength is achieved

between 25-35yrs• Strength decreases around 10% per

decade after 25-30• Primary cause ‘sarcopenia’: 50% reduction in Motor Units 25-

80yrs Loss of muscle mass Loss of Total muscle fibres Reduced muscle X-section Loss of Fast twitch fibres Reduced CNS responses

However, large individual variations – some stronger at 60 than many at 30.

Strength & Ageing

Resistance training can markedly improve strength in both males and females at all ages

Improvements in strength of 50-70yr olds males following resistance training.Many 60yr olds were stronger than 30yr olds

Ageing & Flexibility

• Decrease in passive and active range of movement

• Shortened muscles

• Weaker ligaments, tendons, joint capsule

• Increased likelihood of injury

• Decrease in kinaesthetic awareness

Ageing & Body Composition

• Gradual gain in body weight from 20-70yrs• Decrease in muscle• Increase in fat (subcutaneous, depot, intramuscular &

essential)• Decrease in bone mass (e.g. mineral density)

Hazardous Waste

A cluster of CV risk factors- insulin resistance- hyperinsulinaemia- impaired glucose tolerance or diabetes- raised triglycerides- raised LDLs- decreased HDLs

“Diabesity”

Hazardous Waist

Advancing age – spreading waistline - reduced fitness –

Metabolic Syndrome

Normal

When insulin is bound to the insulin receptor of the cell, glucose can be transported into the cell and be used.

Type 2 Diabetes

• Insulin receptors not functioning

• Insulin cannot bind• Glucose cannot be

transported into the cells

Around 90% of all diabetics are Type 2

Benefits of Exercise for Diabetes

• Improve insulin sensitivity

• Improve glycaemic control

Possible Effects of Ageing on Firefighters

Typical aerobic cost of fire fighting = 35mlsO2/kg/min

To be working at 80-85% of maximum, aerobic capacity needs to be at least 42mlsO2/kg/min

Proposed minimum aerobic fitness standard = 42mlsO2/kg/min

Firefit Steering Group (2007).

Norms for Aerobic Capacity (mlsONorms for Aerobic Capacity (mlsO22/kg/min)/kg/min)Males Age Group

Fitness Rating 15-19 20-29 30-39 40-49 50+

Excellent 60+ 55+ 50+ 46+ 44+

Good 48-59 44-54 39-49 37-45 35-43

Average 39-47 35-43 32-38 30-36 27-34

Below Average 30-38 28-34 22-31 24-29 22-26

Poor <30 <28 <26 <24 <22

Females Age GroupFitness Rating 15-19 20-29 30-39 40-49 50+

Excellent 55+ 50+ 46+ 43+ 41+

Good 44-54 39-49 35-45 34-42 33-40

Average 36-43 32-38 29-34 27-33 26-32

Below Average 29-35 27-31 24-28 22-26 20-25

Poor <29 <27 <24 <22 <20

Sykes 1996

Intense physical activity is a strong triggering factor for heart attack, especially among physically inactive, older and unfit individuals.

100%HRMax

85%HRMax

Heat Stress Tolerance & Ageing• Reduced thermal tolerance

• Reduced sweat production – less heat lost by evaporation

• More susceptible to fatal heat injuries

Ageing & Balance

• Good balance important for operational firefighters -• Working on roofs, smoky places, slippery surfaces while

wearing PPE & BA• Wearing PPE & BA affects functional balance in older

compared to younger firefighters (BA was more a sig. factor).

• Postural balance (with eyes closed) was more negatively affected among the older subjects than the younger ones.

Punakallio et al (2003)  

Dynamic (Functional) & Static (Postural Sway) Balance- general decrease with ageing

An Integrated Workplace Health & Fitness Programmefor Operational & Civilian Staff

….. OH, FBU, HR, H&S and Welfare …..

Cumbria Fire & Rescue Service VO2 Average

35

37

39

41

43

45

47

49

51

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Year

Wholetime Retained Over 40 Under 40 All Staff

• Systematic reduction in sickness rates & injury

• Systematic improvements in BP, BW, BMI, Waist, Lipids, Fitness

Workplace Health & Fitness Programme

Ageing and Firefighter Fitness

• Aerobic Endurance • Strength

• Local Muscle Endurance Flexibility

• Agility & Balance• Body Composition • Metabolic Fitness - Insulin

sensitivity, glucose tolerance, normal BP, heart-healthy blood lipid profiles & fat-burn capability

Ageing & Operational Firefighting

• Age is a poor predictor of job performance among operational firefighters

• Physical fitness and mental abilities showed the strongest relationship with job performance

• These vary greatly across individuals regardless of age

• Increase in MSDs

• Fit note or Sick Note ?

• Gender issues ?

• Importance of Physical Fitness

Trainability & Age

Exercise training improves physiological responses and fitness levels at any age.

37yrs

59yrs

Bill Pearl

Extracurricular Coronary

Firefit Conference 2008Firefit Conference 2008‘Fit for Service, Fit for the Future’‘Fit for Service, Fit for the Future’

Physiology of Ageing- and possible effects on firefighters

Physical Fitness for Firefighting

Kevin SykesKevin Sykes Professor of Occupational Health & FitnessProfessor of Occupational Health & Fitness

DirectorCentre for Exercise & Nutrition Science

University of Chester

k.sykes@chester.ac.uk