• Acute and Chronic Effects of Exercise
• Recommended Physical Activity Program for People with Type 2
• Precautions

• Enhanced muscle glucose uptake (will decrease bG)
• Enhanced insulin sensitivity
  • Those w/ insulin resistance may have only 35-40% of the glucose uptake expected for a given level of plasma insulin
  • Enhanced sensitivity may persist 12-24 hours post-exercise

    Fig 1. Be able to interpret graph below!

    

• Muscle contraction has an 'insulin-like' action
  • Figure 2. (a) Insulin receptor activation stimulates the translocation of GLUT 4 from its intracellular storage site to the plasma membrane pool. (b) Muscle contraction alone, in the absence of insulin, increases GLUT4 translocation (from Ivy, ESSR, 1999)

    

Chronic Effects of Exercise

• Enhanced long-term metabolic control
  • HbA1c will be lower ... Goal is < 7% (DCCT)
• Enhanced insulin sensitivity
  • The ‘chronic effect’ may be in response to multiple ‘acute’ bouts. “Gone in 72 hours!”
• Endurance training is effective!
  • Fig 3. Plasma glucose and insulin response to 100 g OGTT in patients with type II diabetes before and after a 12-month endurance training program (OGTT conducted 18 hours post-exercise). Holloszy et al. Acta Med Scand. 711: 55-65, 1986.

    

• So is resistance training!
  • Fig 4. Glucose infusion rates during last 20 minutes of hyperinsulinemic euglycemic clamp procedure at 2 infusion rates before (open bars) and after (solid bars) 16-wk strength training program. 11 Healthy males 50-65 yrs served as subjects. Miller, J. et al. J Appl Physiol. 77(3): 1122-1127, 1994.

    

• Other Chronic Effects of Exercise
  • Reduced CV risk (lipids, BP)
  • Weight loss
  • Loss of abdominal fat

   

• To summarize: Review carefully the flow chart distributed in class, from Ivy 1999, which illustrates the mechanisms by which exercise enhances long term control in people with diabetes.

Recommended Physical Activity Program

ACSM exercise recommendations for people with diabetes

Frequency:	4-6 d•wk-1, or daily at low to moderate intensity
Intensity:	50-85% VO2 max
Duration:	20-60 min/session
Other:	Maximize caloric expenditure (at least 1000 kcal•wk-1) Use RPE as adjunct to HR monitoring

Resistance training for people with diabetes? Yes with caution.

Mode:	8-10 exercises for all major muscle groups
Dosage:	Minimum of 1 set of 8-12 reps If older (50 yrs plus) or ‘frail’, 10-15 to point of volitional fatigue
Frequency:	2-3 days per week
Other:	F.R.O.M., both concentric, eccentric. Breathing! Training partner

Precautions:

• Exercise same time of day, and avoid late at night
• Monitor glucose before and after
• If your glucose is <100 mg/dl, get some carbs
• Delay exercise if your glucose is uncontrolled (>250 mg/dl)
• Carry identification
• Carry a glucose supplement
• If on insulin:
  • Avoid exercise during peak insulin activity.
  • Insulin dosage reduction are often necessary. Depends on frequency, intensity, duration.
• Use the buddy system
• Foot care
  • SHOES: Expert fit! Support and protection.
  • SOCKS: Wear socks w/ soft, wicking fibers. Change wet socks!
  • SKIN: Coat or cover blister-prone areas
  • TOENAILS: Trim carefully, straight!!!
  • PODIATRIC EXAM once a year!

Diabetic complications/ co-morbid conditions

• Retinopathy: Lifting restrictions (consult opthalmologist).
• Vision impairment: Avoid breath holding and head-down poses.
• Hypertension:Avoid heavy weight lifting exercise, breath holding.
• Nephropathy: As for hypertension
• Peripheral Neuropathy: Foot care! Avoid trauma to feet. Avoid swimming if ulcers present.
• Autonomic Neuropathy: Elevated RHR. Chronotropic insufficiency w/ exercise. Use RPE. Hypoglycemia symptoms masked. Prone to dehydration, thermoregulatory and balance problems.