1. Nutrition, Exercise, & Wellness
Peter WR Lemon
Western University

5. Today’s Talk - Overview
Major Factors Affecting Wellness?
Physical Activity
Nutrition
Sleep
Sitting
Genetics, race, gender, age, etc
Emphasis on objective data (research) as there are lots of conflicting opinions
Behaviour modification
University courses/degrees
review some current topics of interest
questions

6. Sitting

7. The New Smoking!
A recent review of 18 studies (almost 800,000 participants) found prolonged sitting was associated with:
112% increased risk of diabetes
147% increased risk of a heart attack or stroke
90% increased chance of dying via heart attack or stroke
49% increased risk of dying prematurely

8. Solutions
20 – 20 rule (for every 20 minutes of sitting stand for 20 seconds; stand for phone calls; stand during TV commercials)
Regular walks (walk instead of driving; get a dog)
Standing desks
Walking meetings
Use stairs
Regular exercise
although understand that regular exercisers are not immune to sitting disease

9. Benefits of Regular Exercise
decreases all cause mortality
increases cognitive function
reduces degenerative brain disease
improves fat metabolism (favourable blood lipid profile)
improves endothelial (blood vessel) function (reduced hypertension)
reduces pro-inflammatory markers (decreased heart disease & stroke)
improves insulin sensitivity and glucose metabolism (decreased Type 2 diabetes)
reduces cancer incidence
increases ability to perform daily activities
reduces falls (improves balance)
etc, etc

10. What About Effects of Exercise on Obesity?
Despite what many believe regular exercise often does not reduce body fat substantially, especially in women

11. <1.5kg weight loss with 15-52 wk of exercise (endurance)
Short term
<1.5kg weight loss with wk of exercise (endurance)
some of this weight loss could be muscle
low energy (Calorie) dieting can produce short term weight loss but almost always regained over the ensuing 12 months

12. Reasons for Poor Weight Loss
Gender/Individual variation
Compensation
increased energy intake
decreased spontaneous activity
reduced metabolic rate at rest
Exercise Type
may affect resting & post exercise metabolism differently
Endurance vs Strength; High Intensity Interval (HIIT); Sprint Interval (SIT) exercise
~200 – 400
Calories/h
~1200 Calories

13. Reasons for Poor Weight Loss
Weight cycling
one significant weight loss & regain makes the next attempt more difficult & weight regain is much faster
Why?
loss is both muscle & fat while regain is fat
multiple loss/regain leads to increased obesity & > cardiovascular disease than obese who never lost weight

14. Sleep and Obesity

15. Sleep Duration and Body Fat Loss (Nedeltcheva et al, 2010)
10 overweight participants (BMI =27.4; weight (kg) / height (metres)2
7 men, 3 women; aged 41±5 y
sleep duration = 7.7 hours/night
manipulated sleep duration for 2 weeks:
1) 8.5 h sleep
2) 5.5 h sleep
fed a low energy (Calorie) diet
1447 ± 227 vs 1450 ± 236 Calories/day (90% Resting Metabolic Rate)
controlled energy output to generate a deficit
2136 ± 342 vs 2139 ± 393 Calories/day (measured with doubly labelled water)

16. Measured body composition (DEXA)
2 week weight loss was similar in both groups but importantly ....
the 8.5 h sleepers lost:
133% more fat (1.4 vs 0.6 kg fat) & 60% less muscle (1.5 vs 2.4 kg)
Why?
short sleepers were hungrier and utilized less fat for energy due to hormonal changes

17. Sleep
< 8 hours alters gut hormones (leptin, ghrelin) increasing appetite, insulin resistance, fat storage, and reducing lipolysis (fat mobilization from fat stores)

18. Energy (Calorie) Restriction (CR)
CR (~30%) extends length of life in a variety of organisms (fruit flies, worms, rodents, even monkeys)
CR also increases a number of health benefits
 BP, insulin, diabetes, LDL-C, CAD, cancer, body mass, body fat, muscle mass
however, difficult to maintain long term so perhaps impractical

19. Intermittent Fasting (IF)
IF is a variation of CR that is more practical
1 or 2 d/wk (5:2)
alternate days
within one day (fast 16 hours and eat 8h)
interesting because probably more like how our hunter-gatherer ancestors ate
low calorie drinks and water allowed (important to avoid dehydration)
often some supplemental nutrients (BCAA, medium chain fats) taken to preserve muscle and increase satiety

20. 13% Fat, 58% CHO, 29% PRO
61% Fat, 21% CHO, 18% PRO

21. Food Intake (similar across groups)
Body Mass
(> in FA; NA > NT)

23. Effects on Fuel Use/Metabolism?

24. Glucose/Insulin?
- = overnight fast
+ = 1 h after glucose infusion

25. How does IF Work? Conclusion
Continuous feeding perturbs a number of metabolic signaling molecules which predisposes one to obesity and metabolic disease.
Conclusion
Insufficient long term data in humans but available data suggest IF has significant potential.

26. IF and the Brain improves cognitive function
increases variety of neurotrophic factors in the brain similar to exercise
perhaps a challenge to which the brain adapts
Timing of IF
Breakfast skipping vs dinner skipping
Thermic effect of food
Insulin resistance

29. Sprint or High Intensity Interval Exercise Training
3 sessions/wk
10-30 sec sprints (4-10 repeats)
separated by 2-4 min rest breaks
~10-30 minutes (2-5 min of actual exercise)
produces rapid adaptations (similar or > endurance exercise)

30. High Intensity Interval (HIIT) or Sprint Interval (SIT) Exercise

31. Constant Rate vs Increasing/Decreasing

32. Typical Response

33. Sprint vs Endurance Training
Exercise Intensity
Jogging Pace
Max Speed Run
Exercise Session
Continuous
for min
4-6, 30 sec bouts with 4 min rec
Duration/session
30-60 min
2-3 min
Training Program
3/wk for 6 wk
Ex Duration/wk
1.5-3 hours
6-9 min
Ex Duration/6wk
13.5 hours
45 min
MacPherson, Hazell, Olver, Paterson, Lemon 2011

34. Exercise Performance Adaptations
Gibala et al (2006)

35. MacPherson et al (2011)

36. Hazell, MacPherson, Gravelle, Lemon (2010)

37. MacPherson et al (2011)

38. Exercise Adherence
Endurance exercise programs have high drop out rates (~50% in the first 6 months)
Despite much greater exercise intensity sprint interval programs have much higher adherence (100% vs 0%)
Why?
unknown at present
perhaps reduced time commitment
perhaps some physiological/biochemical reason
regardless this is significant given health problems associated with sedentary living

39. Summary Important Factors Affecting Wellness under your Control
Physical Activity
Nutrition
Sleep
Sitting
to find out more enter “Pubmed” into Google and enter a few key words