Tag Archives: exercise

Exercise and the PWD (Person With Diabetes)

hypoglycemia, woman, rock-climbing

Hypoglycemia now would be a tad inconvenient

People with diabetes may have specific issues that need to be taken into account when exercising.

DIABETIC RETINOPATHY

Retinopathy, an eye disease caused by diabetes, increases risk of retinal detachment and bleeding into the eyeball called vitreous hemorrhage. These can cause blindness. Vigorous aerobic or resistance training may increase the odds of these serious eye complications. Patients with retinopathy may not be able to safely participate. If you have any degree of retinopathy, avoid the straining and breath-holding that is so often done during weightlifting or other forms of resistance exercise. Vigorous aerobic exercise may also pose a risk. By all means, check with your ophthalmologist first. You don’t want to experiment with your eyes.

DIABETIC FEET AND PERIPHERAL NEUROPATHY

Diabetics are prone to foot ulcers, infections, and ingrown toenails, especially if peripheral neuropathy (numbness or loss of sensation) is present. Proper foot care, including frequent inspection, is more important than usual if a diabetic exercises with her feet. Daily inspection should include the soles and in-between the toes, looking for blisters, redness, calluses, cracks, scrapes, or breaks in the skin. See your physician or podiatrist for any abnormalities. Proper footwear is important (for example, don’t crowd your toes). Dry feet should be treated with a moisturizer regularly. In cases of severe peripheral neuropathy, non-weight-bearing exercise (e.g., swimming or cycling) may be preferable. Discuss with your physician or podiatrist.

HYPOGLYCEMIA

Low blood sugars are a risk during exercise if you take diabetic medications in the following classes: insulins, sulfonylureas, meglitinides, and possibly thiazolidinediones and bromocriptine.

Hypoglycemia is very uncommon with thiazolidinediones. Bromocriptine is so new (for diabetes) that we have little experience with it; hypoglycemia is probably rare or non-existent. Diabetics treated with diet alone or other medications rarely have trouble with hypoglycemia during exercise.

Always check your blood sugar before an exercise session if you are at risk for hypoglycemia. Always have glucose tablets, such as Dextrotabs, available if you are at risk for hypoglycemia. Hold off on your exercise if your blood sugar is over 200 mg/dl (11.1 mmol/l) and you don’t feel well, because exercise has the potential to raise blood sugar even further early in the course of an exercise session.

As an exercise session continues, active muscles may soak up bloodstream glucose as an energy source, leaving less circulating glucose available for other tissues such as your brain. Vigorous exercise can reduce blood sugar levels below 60 mg/dl (3.33 mmol/l), although it’s rarely a problem in non-diabetics.

The degree of glucose removal from the bloodstream by exercising muscles depends on how much muscle is working, and how hard. Vigorous exercise by several large muscles will remove more glucose. Compare a long rowing race to a slow stroll around in the neighborhood. The rower is strenuously using large muscles in the legs, arms, and back. The rower will pull much more glucose out of circulation. Of course, other metabolic processes are working to put more glucose into circulation as exercising muscles remove it. Carbohydrate consumption and diabetic medications are going to affect this balance one way or the other.

If you are at risk for hypoglycemia, check your blood sugar before your exercise session. If under 90 mg/dl (5.0 mmol/l), eat a meal or chew some glucose tablets to prevent exercise-induced hypoglycemia. Re-test your blood sugar 30–60 minutes later, before you exercise, to be sure it’s over 90 mg/dl (5.0 mmol/l). The peak effect of the glucose tablets will be 30–60 minutes later. If the exercise session is long or strenuous, you may need to chew glucose tablets every 15–30 minutes. If you don’t have glucose tablets, keep a carbohydrate source with you or nearby in case you develop hypoglycemia during exercise.

Re-check your blood sugar 30–60 minutes after exercise since it may tend to go too low.

If you are at risk of hypoglycemia and performing moderately vigorous or strenuous exercise, you may need to check your blood sugar every 15–30 minutes during exercise sessions until you have established a predictable pattern. Reduce the frequency once you’re convinced that hypoglycemia won’t occur. Return to frequent blood sugar checks when your diet or exercise routine changes.

These general guidelines don’t apply across the board to each and every diabetic. Our metabolisms are all different. The best way to see what effect diet and exercise will have on your glucose levels is to monitor them with your home glucose measuring device, especially if you are new to exercise or you work out vigorously. You can pause during your exercise routine and check a glucose level, particularly if you don’t feel well. Carbohydrate or calorie restriction combined with a moderately strenuous or vigorous exercise program may necessitate a 50 percent or more reduction in your insulin, sulfonylurea, or meglitinide. Or the dosage may need to be reduced only on days of heavy workouts. Again, enlist the help of your personal physician, dietitian, diabetes nurse educator, and home glucose monitor.

Finally, insulin users should be aware that insulin injected over muscles that are about to be exercised may get faster absorption into the bloodstream. Blood sugar may then fall rapidly and too low. For example, injecting into the thigh and then going for a run may cause a more pronounced insulin effect compared to injection into the abdomen or arm.

medical clearance, treadmill stress test

This treadmill stress test is looking for hidden heart disease

AUTONOMIC NEUROPATHY

This issue is pretty technical and pertains to function of automatic, unconscious body functions controlled by nerves. These reflexes can be abnormal, particularly in someone who’s had diabetes for many years, and are called autonomic neuropathy. Take your heart rate, for example. It’s there all the time, you don’t have to think about it. If you run to catch a bus or climb two flights of stairs, your heart rate increases automatically to supply more blood to exercising muscles. If that automatic reflex doesn’t work properly, exercise is more dangerous, possibly leading to passing out, dizziness, and poor exercise tolerance. Other automatic nerve systems control our body temperature regulation (exercise may overheat you), stomach emptying (your blood sugar may go too low), and blood pressure (it could drop too low). Only your doctor can tell for sure if you have autonomic neuropathy.

Steve Parker, M.D.

But, Doc, My Back and Joints Hurt Too Much To Exercise!

EXERCISE WITH JOINT AND BACK PAIN

Many of my obese patients have chronic low back and joint pains.  Painful lower limb joints and chronic or recurrent back pain are an exercise barrier to many people, whether skinny or fat. Those affected should consult a physician for a diagnosis, treatment, and advice on appropriate physical activity. If the physician isn’t sure about an exercise prescription, consultation with an orthopedist, physiatrist, or physical therapist should be helpful. Generally, weight-bearing on bad joints should be minimized by doing pool calisthenics, stationary cycling, swimming, etc. Use your imagination. Particularly bothersome joints may not tolerate exercise, if ever, until weight is lost by some method other than exercise. (Exercise by itself is typically an ineffective way to lose major weight.)

Light to moderate exercise actually reduces the pain and disability of knee degenerative arthritis. The effect is modest and comes with a small risk of injury such as bone fracture, cartilage tears, arthritis flare, and soft tissue strain.

Physical Activity Reduces Prostate Cancer Risk

…according to an article in MedPageToday.

Not Darrin Carlson

Yet another reason to work out

In a forward-looking study, white men suspected of prostate cancer and scheduled for biopsy were less likely to have the disease if they were at least moderately active, according to Lionel Bañez, MD, of the Durham Veterans Affairs Medical Center in Durham N.C., and colleagues.

If they did have cancer, they were significantly less likely to have high-grade disease if they had been working out regularly, Bañez and colleagues reported  in Cancer.

Another way to reduce your risk of prostate cancer is to follow the Mediterranean diet.  Other cancers reduced by the Mediterranean diet are breast, colo-rectal, and uterus.

The association of exercise and lower prostate cancer risk was not noted in black men, for unclear reasons.

Resistance Versus Aerobic Training: Which Is Better?

iStock_000007725919XSmall

Weight training, also known as resistance training, may be just as effective as, or even superior to, aerobic training in terms of overall health promotion.  Furthermore, it’s less time-consuming according to a 2010 review by Stuart Phillips and Richard Winett.

I don’t like to exercise but I want the health benefits.  So I look for ways to get it done quickly and safely.

Here’s a quote from Phillips and Winett:

A central tenet of this review is that the dogmatic dichotomy of resistance training as being muscle and strength building with little or no value in promoting cardiometabolic health and aerobic training as endurance promoting and cardioprotective, respectively, largely is incorrect.

Over the last few years (decade?), a new exercise model has emerged.  It’s simply intense resistance training for 15–20 minutes twice a week.  It’s not fun, but you’re done and can move on to other things you enjoy.  None of this three to five hours a week of exercise some recommend.  We have no consensus on whether the new model is as healthy as the old.

More tidbits from Phillips and Winett:

  • they hypothesize that resistance training (RT) leads to improved physical function, fewer falls, lower risk for disability, and potentially longer life span
  • only 10–15% of middle-aged or older adults in the U.S. practice RT whereas 35% engage in aerobic training (AT) or physical activity to meet minimal guidelines
  • they propose RT protocols that are brief, simple, and feasible
  • twice weekly training may be all that’s necessary
  • RT has a beneficial effect on LDL cholesterol and tends to increase HDL cholesterol, comparable to effects seen with AT
  • blood pressure reductions with RT are comparable to those seen with AT (6 mmHg systolic, almost 5 mmHg diastolic)
  • RT improves glucose regulation and insulin activity in those with diabetes and prediabetes
  • effort is a key component of the RT stimulus: voluntary fatigue is the goal (referred to as “momentary muscular failure” in some of my other posts)
  • “In intrinsic RT, the focus and goal are to target and fatigue muscle groups.  A wide range of repetitions and time under tension can be used to achieve such a goal.  Resistance simply is a vehicle to produce fatigue and only is adjusted when fatigue is not reached within the designated number of repetitions and time under tension.”

Our thesis is that an intrinsically oriented (i.e., guided by a high degree of effort intrinsic to each subject) program with at minimum of one set with 10–15 multiple muscle group exercises (e.g., leg press, chest press, pulldown, overhead press) executed with good form would be highly effective from a public health perspective.

The authors cite 60 other sources to support their contentions.

These ideas are the foundation of time-efficient resistance training of the sort promoted by Dr. Doug McGuff, Skyler Tanner, Fred Hahn, Chris Highcock, James Steele II, and Jonathan Bailor, to name a few.

Only a minority will ever exercise as much as the public health authorities recommend.  This new training model has real potential to help the rest of us.

For folks with diabetes, the combination of aerobic and resistance training may be better than either alone, for control of glucose levels.

Steve Parker, M.D.

Reference:  Phillips, Stuart and Winett, Richard.  Uncomplicated resistance training and health-related outcomes: Evidence for a public health mandate.  Current Sports Medicine Reports, 2010, vol. 9 (#4), pages 208-213.

Do You Need Medical Clearance Before Starting an Exercise Program?

medical clearance, treadmill stress test

This treadmill stress test is looking for hidden heart disease

To protect you from injury, I recommend that you obtain “medical clearance” from a personal physician before starting an exercise program. A physician is in the best position to determine if your plans are safe for you, thereby avoiding complications such as injury and death. Nevertheless, most adults can start a moderate-intensity exercise program with little risk. An example of moderate intensity would be walking briskly (3–4 mph or 4.8–6.4 km/h) for 30 minutes daily.

Men over 40 and women over 50 who anticipate a more vigorous program should consult a physician to ensure safety. The physician may well recommend diagnostic blood work, an electrocardiogram (heart electrical tracing), and an exercise stress test (often on a treadmill). The goal is not to generate fees for the doctor, but to find the occasional person for whom exercise will be dangerous, if not fatal. Those who drop dead at the start of a vigorous exercise program often have an undiagnosed heart condition, such as blockages in the arteries that supply the heart muscle. The doctor will also look for other dangerous undiagnosed “silent” conditions, such as leaky heart valves, hereditary heart conditions, aneurysms, extremely high blood pressure, and severe diabetes.

She looks healthy enough, but how can you be sure?

She looks healthy enough, but how can you be sure?

The American Diabetes Association’s Standards of Care—2011 states that routine testing of all diabetics for heart artery blockages before an exercise program is not recommended; the doctor should use judgment case-by-case. Many diabetics (and their doctors) are unaware that they already have “silent” coronary artery disease (CAD). CAD is defined by blocked or clogged heart arteries, which reduced the blood flow to the hard-working heart muscle. Your heart pumps 100,000 times a day, every day, for years without rest. CAD raises the odds of fainting, heart attack, or sudden death during strenuous exercise. I recommend a cardiac stress test (or the equivalent) to all diabetics prior to moderate or vigorous exercise programs, particularly if over 40 years old. CAD can thus be diagnosed and treated before complications arise. Ask your personal physician for her opinion.

Regardless of age and diabetes, other folks who may benefit from a medical consultation before starting an exercise program include those with known high blood pressure, high cholesterol, joint problems (e.g., arthritis, degenerated discs), neurologic problems, poor circulation, lung disease, or any other significant chronic medical condition. Also be sure to check with a doctor first if you’ve been experiencing chest pains, palpitations, dizziness, fainting spells, headaches, frequent urination, or any unusual symptoms (particularly during exertion).

Physicians, physiatrists, physical therapists, and exercise physiologists can also be helpful in design of a safe, effective exercise program for those with established chronic medical conditions.

Steve Parker, M.D.

Ever Heard of “Interval Walking”? You Need To Know About It!

Not ready for this? Consider interval walking then.

Not ready for this? Consider interval walking then.

Compared to a regular continuous walking program, interval walking is superior for improving physical fitness, body composition (body mass and fatness), and blood sugar control according to new research reported in Diabetes Care.  Study participants were type 2 diabetics.

Training groups were prescribed five sessions per week (60 min/session) and were controlled with an accelerometer and a heart-rate monitor. Continuous walkers performed all training at moderate intensity, whereas interval walkers alternated 3-min repetitions at low and high intensity. Before and after the 4-month intervention, the following variables were measured: VO2max, body composition, and glycemic control (fasting glucose, HbA1c, oral glucose tolerance test, and continuous glucose monitoring.

I haven’t read the full report yet, but expect that the interval walkers walked as fast as they could for three minutes (4 mph?) then slowed down to a comfortable stroll (1–2 mph?) for three minutes, alternating thusly for 60 minutes.

This should easily do-able for nearly all type 2 diabetics.  The reported results jive with other studies of more vigorous and intimidating interval training.  The only caveat is that it was a small pilot study that may or may not be reproducible.

Steve Parker, M.D.

Surprising Results of a Three-Week Fitness Lay-Off

MP900182524[1]I’m reminded of a quote from a famous violinist: “If I don’t practice for one day, I can tell.  If I don’t practice for two days, my conductor can tell.  If I don’t practice for three days, the audience can tell.”

A few months ago, I laid off all exercise for three weeks straight, partly due to a long vacation, partly to see how much my fitness would deteriorate.

Here’s what I found:

  • My time for the one-mile run increased from 8 mins and 54 seconds to 9 mins and 30 seconds
  • My maximum number of push-ups increased from 32 to 36
  • My maximum number of sit-ups increased from 32 to 34
  • My maximum number of pull-ups increased from 8 to 9

CLOSING THOUGHTS

Strength measures increased, surprisingly.  Was it just a good day, or did my muscles need the time off to rest and re-build?  Over-training is a real problem for some folks.  At 20 minutes of weight-training twice a week, I doubt I was anywhere near what most consider over-training.  I don’t fiddle-fart around during my exercise sessions, but I’m not puking either.

So I won’t feel too bad in the future if I take a couple or three weeks off from strength training periodically.

My endurance for running deteriorated significantly.  Is it related to the lack of strength training, the lack of treadmill interval work, or both?

Your mileage will vary.

Steve Parker, M.D.

Paleo Pioneer S. Boyd Eaton’s Personal Lifestyle

African Savanna

African Savanna

Dr. Eaton (M.D.) spoke at the last Ancestral Health Symposium about his own diet and exercise program.  He’s 74-years-old and has been following his paleo lifestyle for 30 years.  In this video, Dr. Eaton looks quite fit and is obviously mentally sharp.

He talks about a “weak form” of the paleo diet that would include relatively small amounts of whole grains (e.g., shredded wheat) and dairy (e.g., skim milk).  He doesn’t proscribe beans.  He limits saturated fat, but enjoys red wine.

Dr. Eaton also discusses a “strong form” diet that would cut out the dairy, grains, and probably alcohol.  This is for those with certain diseases of modern civilization, such as high blood pressure, coronary artery disease, metabolic syndrome, adverse blood lipids, etc.  He didn’t mention diabetes specifically, but I bet he would include it in the list.

He has an impressive daily exercise program that probably takes at least an hour, with weight training on machines plus an aerobics (stationary bike and swimming).

Dr. Eaton supplments with a multivitamin/multimineral (showed a picture of Centrum), EPA/DHA, and fiber (especially soluble fiber).

The video is only 20 minutes long and well worth a look.

Steve Parker, M.D.

h/t Melissa McEwen. (Melissa has the impression the Eaton partakes of whole grains and dairy.  I didn’t hear that in the video but may have missed it.)

 

QOTD: All You Need Is a Single Set of Reps

We recommend that appreciably the same muscular strength and endurance adaptations can be attained by performing a single set of ~8-12 repetitions to momentary muscular failure, at a repetition duration that maintains muscular tension throughout the entire range of motion, for most major muscle groups once or twice each week. All resistance types (e.g. free-weights, resistance machines, bodyweight, etc.) show potential for increases in strength, with no significant difference between them, although resistance machines appear to pose a lower risk of injury.

Fisher, James, et al. Evidence-based resistance training recommendations. Medicina Sportiva, 15 (2011): 147-162.

Random Thoughts On Fitness

A couple years ago, I was thinking about putting together a fitness program for myself.  My goals were endurance, strength, less low-back aching, flexibility, longevity, and being able to get on my horse bareback without a mounting block or other cheat.

I spent quite a bit of time at Doug Robb’s HeathHabits site.  He has a post called The “I don’t have time to workout” Workout.  I ran across some paper notes I made during my time there.  Doug recommended some basic moves to incorporate: air squat, Hindu pushup, dragon flag, shuffle of scissor lunge, Spiderman lung, hip thrust/bridge, swing snatch, dumbbell press, Siff lunge, jumping Bulgarian squat, band wood chops, stiff leg deadlift.  Click the link to see videos of most of these exercises.  The rest you can find on YouTube.

Another post is called “Do you wanna get big and strong? -Phase 1”.  The basic program is lifting weights thrice weekly.  Monday, work the chest and back.  Tuesday, legs and abs/core.  Friday, arms and shoulders.

  • Chest exercises: presses (barbell or dumbell, incline, decline, flat, even pushups with additional resistance  – your choice
  • Back: chins or rows
  • Legs: squats or deadlifts
  • Arms and shoulders: dips, presses, curls

Doug is a personal trainer with a huge amount of experience.  He’s a good writer, too, and gives away a wealth of information at his website.

Around this same time of searching a couple years ago, I ran across Mark Verstegen’s Core Performance, Mark Lauren’s book “You Are Your Own Gym,”  and Mark Sisson’s free fitness ebook that also  features bodyweight exercises. Lauren is or was a Navy Seal trainer.  His plan involves 30 minutes of work on four days a week and uses minimal equipment.  Lots of good reviews at Amazon.com.

I did the Verstegen program for 15 weeks and saw major improvements in my fitness and low-back aching.  It’s a good program.  The only drawback is that it required six hours a week of my time.

Newbies to vigorous exercise should seriously consider using a personal trainer.

If you’ve had any experience with these regimens, please share.  Or is there another you like?

Steve Parker, M.D.