Lifestyle: Physical Activity

Question 1

**

Best prescription to cure/ prevent diabetes

Answer 1

walking 30 min a day
* Control went on with normal life nd highest prevalence
* Metformin had about 31% reduction
* Lifestyle has even better effect about 60% reduction in instance of diabetes

Question 2

Why are metformin and lifestyle not additive?

Answer 2

Both act through the same pathway on AMPK

Question 3

What is an important consideration for those who want to undertake vigorous exercise with T2D?

Answer 3

People with cardiovascular disease or microvascular complications of diabetes, who wish to undertake exercise that is substantially more vigorous than brisk walking, should have medical evaluation for conditions that might increase exercise-associated risk.
* May have underlying conditions hence why brisk walking is the best

Question 4

What are problems doctors face in reccomending PA and solutions?

Answer 4

Question 5

What was developed to help physicians prescribe exercise?

Answer 5

Question 6

What is the goal for PA?

Answer 6

Individuals should strive to achieve 150 minutes per week of moderate-intensity PA combined with 2 days per week of vigorous-intensity PA

Question 7

Immediate benefits of PA

Answer 7

• lower blood glucose within 1 hour
• improve mood, sleep patterns and energy levels
• Increase effectiveness of insulin your body makes or the insulin your doctor prescribed to you

Question 8

Long-term benefits of PA

Answer 8

• Improve blood glucose control (HbA1c)
• reduce you body fat
• help keep pancreas, kidneys, eyes and nerves healthy
• reduce the risk of heart attack, stroke and death

Question 9

Describe the graph

Answer 9

the more obese and less PA the more years of life that are lost

Question 10

What is the dose relationship between PA and heart failure?

Answer 10

The higher amount of PA the less risk for CVD

Question 11

What are the goals of aerobic training and resistance training?

Answer 11

• Aerobic training: goal is to increase aerobic capacity (max oxygen uptake), eg. running
• Resistance training: goal is to increase muscle mass, eg. weight lifting

Question 12

What factors saw significant differences with AT or RT?

Answer 12

• TG: RT, combined vs. AT
• lean mass: RT, combined vs. AT
• abdominal visceral fat: AT

Question 13

Is AT or RT better?

Answer 13

The combination of PA and reduced energy intake has been found to be more effective than either alone.
* AT is more effective then RT

Question 14

What are the benefits of PA on T2D?

Answer 14

• Decreases body weight
• Displays protective cardiovascular effects both during exercise as well as at rest → increase in stroke volume, lower resting heart rate, lower blood pressure
• Increases insulin sensitivity
• Stimulates mitochondria biogenesis
• Regulates fat metabolism / TG oxidation
• Stimulates thermogenesis
• Produces different myokines, which in turn promote angiogenesis, neuroprotection, etc.
• Increases bone density

Question 15

How does PA improve glucose uptake?

Answer 15

Both methods can stimulate pathways of glucose uptake but bypasses the need for insulin
* Mechanical stretch: PA is mechanical so with muscle contraction there is a mechanical stretch which activates signalling pathway to translocate GLUT4, so if insulin resistance is not responding, PA will still transfer GLUT4 to membrane to uptake glucose and therefore glucose disposal.
* Sensing of energy levels: As you work you use ATP to contract muscles and increase AMP/ATP which can activate AMPK and can also translocate GLUT4

Blood flow also increases allowing for better flow of glucose to cells for uptake

Question 16

How does PA effect glycogen and mitochondria?

Answer 16

cAMP activity increases in response to PA
* cAMP stimulate PKA which then stimulates phosporylase a thus breaking down glycogen to glucose for short-term use. PKA additionally inhibits synthase b, preventing glycogensis
* cAMP → AMP → ↑ AMP/ATP whih stimulate AMPK and this stimulate GLUT4 translocation but also stimulates PGC1a for mito biogenesis for long-term glucose decrease by having more to to utilize glucose during exercise.

Question 17

How was skeletal muscle discovered to be an endocrine organ?

Answer 17

Myostatin was the first identified myokine in 1997. The concept of myokine was proposed in 2003 when it became apparent that the skeletal muscle possessed endocrine properties and communicated with other organs.

Question 18

What are hallmark myokines of the muscle?

Answer 18

• Cytokines (IL6, IL8, IL15, …)
• Growth factors (BDNF, FGF21,…)
• Other molecules (Irisin, musclin,…)

Question 19

Role if Irisin and effect of PA

Answer 19

Muscle secretes irisin hormone with PA which signals adipose tissue to convert white fat to brown fat which is more beneficial because it produces heat and burns calories only for heat.
* increases lipolysis
* may signal neurogensis in the brain

Question 20

Role of FGF21 growth factor and effect of PA

Answer 20

Acts on tissues (mainly adipocytes) to regulate glucose uptake, fatty acid oxidation and inhibit lipogensis by acting on its receptors
* With obesity FGF21 becomes resistance increasing circulating levels
* PA may improve its activity

Question 21

Effect of PA on IGF/PI3K/Akt

Answer 21

• stimulates muscle vascularization to increase blood flow and thus more oxygen to muslce by creating new vessels (via VEGF & Fstl1/NOS)
• stimulates FGF21

Question 22

Effect of PA on PGC-1

Answer 22

With PA, PGC-1 is stimulated by cAMP cascade and get more mitogenesis

Question 23

Effect of PA in myostatin

Answer 23

PA inhibits secretion of myostatin so can build more muscle cells

Question 24

Effect of PA on BNDF

Answer 24

• goes to brain and improves neuroplasticity
• stimulates AMPK to increase fat oxidation, glucose uptake, and myogenesis
• may improve motor unit regeneration

Question 25

How does training adapt muscle to a healthy phenotype?

Answer 25

up-regulation of stress proteins (HO-1, HSPs)
* mitochondriogenesis (pGC-1a up-regulation)
* muscle hypertrophy
* angiogenesis

Question 26

How does training improve anti-oxidants?

Answer 26

↑ antioxidant network in several tissues: upregulation of antioxidant enzymes/ proteins such as SOD, GPx, GCS, CAT, HO-1, HSP70
* blood, brain, liver, kidneys, gut, muscle fibres, vessels, heart

Question 27

Overall effect of myokines

Answer 27

Question 28

Is nutrition or PA more potent in reducing anthropometrics of T2D?

Answer 28

Dietary interventions alone are better with a greater effect on weight, BMI, waist circumference, and body fat than PA alone
* PA is still beneficial but produces only modest weight loss
* Together diet and PA is additive