Nutrition, Exercise, & Wellness Peter WR Lemon Western University

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

Sitting

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

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

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

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

<1.5kg weight loss with 15-52 wk of exercise (endurance) Short term <1.5kg weight loss with 15-52 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

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

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

Sleep and Obesity

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)

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

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

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

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

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

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

Effects on Fuel Use/Metabolism?

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

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.

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

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)

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

Constant Rate vs Increasing/Decreasing

Typical Response

Sprint vs Endurance Training Exercise Intensity Jogging Pace Max Speed Run Exercise Session Continuous for 30-60 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

Exercise Performance Adaptations Gibala et al (2006)

MacPherson et al (2011)

Hazell, MacPherson, Gravelle, Lemon (2010)

MacPherson et al (2011)

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

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