Tag Archives: exercise

High-Intensity Interval Training: A Primer and the Science Behind It

A treadmill is one of many ways to do high-intensity interval training.  Tabata's classic study used a stationary bicycle.

A treadmill is one of many ways to do high-intensity interval training. Tabata’s classic study used a stationary bicycle.

I found a free article by Martin Gibala,Ph.D., a major researcher into high-intensity interval training (HIIT).  He prefers to abbreviate it as HIT.

I don’t like to exercise, so I’ve been incorporating HIIT into my workouts for over a year.  It’s helped me maintain my level of fitness to that required of U.S. Army soldiers, without being a exercise fanatic.

So what’s HIIT?  Gibala’s definition:

High-intensity interval training is characterized by repeated sessions of relatively brief, intermittent exercise, often performed with an “all out” effort or at an intensity close to that which elicits peak oxygen uptake (i.e., ≥90% of VO2peak).

HIIT involves short sessions of very intense exercise about three times per week, for as little as 15 minutes.  That’s total time, not 15 minutes per session!  Yet you see a significant fitness improvement.  Be aware: the brief exercise bouts should be exhausting.

The Gibala article has all the scientific journal references you’d want, plus a suggested HIIT program for an absolute beginner.

One final quote from Dr. Gibala:

It is unlikely that high-intensity interval training produces all of the benefits normally associated with traditional endurance training. The best approach to fitness is a varied strategy that incorporates strength, endurance and speed sessions as well as flexibility exercises and proper nutrition. But for people who are pressed for time, high-intensity intervals are an extremely efficient way to train. Even if you have the time, adding an interval session to your current program will likely provide new and different adaptations. The bottom line is that — provided you are able and willing (physically and mentally) to put up with the discomfort of high-intensity interval training — you can likely get away with a lower training volume and less total exercise time.

Read the rest.

Steve Parker, M.D.

PS:  Why won’t Gibala give some credit to Izumi Tabata who did a pioneering study on HIIT in 1996?

PPS:  Gibala narrated this stationary bike HIIT video.

h/t Tony Boutagy

Exercise Isn’t Supposed To Be Fun

MP900049602Melanie Thomassian’s recent blog post on physical activity reminded me of a Ken Hutchins essay called “Exercise vs Recreation.”

One of the key take-away points of the essay for me is that exercise isn’t supposed to be fun.  Ken wrote, “Do not try to make exercise enjoyable.”  Getting your teeth cleaned isn’t supposed to be fun, either.

Once I got that through my thick skull, it made it easier for me to slog through my  twice weekly workouts.  Another excerpt:

We accept that both exercise and recreation are important in the overall scheme of fitness, and they overlap to a great degree.  But to reap maximum benefits of both or either they must first be well-defined and then be segregated in practice.

Read the whole thing.

I’m Still As Fit As a U.S. Army Soldier

"Good job, maggot!"

“Good job, maggot!”

I took the Army Physical Fitness Test last week, and passed.  I’m only working out for 35 minutes twice a week, with a combination of weight training and high intensity interval training on a stationary bicycle.  (The weight training is much like this program.)

U.S. soldiers, at least those in the Army, have to pass a physical fitness test twice a year.  I wondered how I, at 58-years-old, stacked up so I self-administered the three fitness components.  I didn’t run in army boots, nor carry a rifle or backpack!  Soldiers need to score a minimum of 60 points on each exercise.

The Army Physical Fitness Test (APFT) performance requirements are adjusted for age and sex.

My Results

  • two-mile run: 19 minutes, 20 seconds (65 points)
  • consecutive military sit-ups: 41 (75 points)
  • consecutive push-ups: 32 (76 points)

Compared to my performance in August 2012, my run took 102 seconds longer, I increased my sit-ups by 9, and my push-ups held steady.

I purposefully “held back” on running because I remembered how bad I felt after the run last August.  Even this time I had a little hamstring strain.  Nevertheless, I suspect my aerobic endurance is truly less now since I’m riding the stationary bike instead of running the treadmill.  The bike exercise is more enjoyable.  My knees will thank me over the long-run.

I’m satisfied with this level of fitness.  It’s a good base for some strenuous hiking I’ll be doing over the next few months.  With a little luck, I’ll be hiking the Grand Canyon rim-to-rim with my son’s Boy Scout troop in May.


Gretchen Reynolds Argues That Four Workouts a Week May Be Better Than Six

I wonder if two is just as good as four.  Details at the New York Times.

Are Two Days of Exercise a Week as Good as Six?

exercise for weight loss and management, dumbbells

If you’re not familiar with weight training, a personal trainer is an great idea

Weight Maven Beth Mazur  found evidence in favor of the fewer days, at least in post-menopausal women.

I don’t like to exercise.  Sometimes I find excuses to avoid even my twice weekly 40-minute workouts.

You may well have good reasons to exercise every day.  Maybe you’re a competitive athlete or enjoy exercise.  If you just want the health benefits of exercise, I’m increasingly convinced that twice a week is enough.

Prolonged Sitting Is the New Trans Fat: Avoid It

Within the last couple months I read somewhere that the adverse health effects of sitting all day long are not counteracted by an hour of vigorous exercise.  If true, that’s disappointing to many of us.

I think this is the research report that got the buzz going.

The investigators suggest you’re better off with four hours of standing and two hours of walking.  Easy peasy, right?

Some caveats.  It’s a very short-term small study of young adults (18 initially but three dropped out).  The “prolonged sitting” regime lasted 14 hours.   The health focus of the study was limited to insulin levels, insulin sensitivity, blood sugar levels, and blood lipids like cholesterol and triglycerides.

Where did I read, “Sitting is the new saturated fat”?

The investigators conclude…

One hour of daily physical exercise cannot compensate the negative effects of inactivity on insulin level and plasma lipids if the rest of the day is spent sitting. Reducing inactivity by increasing the time spent walking/standing is more effective than one hour of physical exercise, when energy expenditure is kept constant.

The Washington Post in July, 2011, had an article along the same lines (h/t Beth Mazur).

—Steve Parker, M.D.

Reference:  Duvivier BMFM, Schaper NC, Bremers MA, van Crombrugge G, Menheere PPCA, et al. (2013) Minimal Intensity Physical Activity (Standing and Walking) of Longer Duration Improves Insulin Action and Plasma Lipids More than Shorter Periods of Moderate to Vigorous Exercise (Cycling) in Sedentary Subjects When Energy Expenditure Is Comparable. PLoS ONE 8(2): e55542. doi:10.1371/journal.pone.0055542

Does Strength Training Affect Aging?

Skyler Tanner is one of my favorite bloggers.  Watch his video for his answer.

Regular Exercise Linked to Lower Prostate Cancer Risk

…according to an article in MedPageToday.  The association was not noted in black men, however.

In a prospective study, Caucasian 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 online 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.


Resistance Versus Aerobic Training


Resistance or weight training may be just as effective as, or even superior to, aerobic training in terms of overall health promotion.  Plus, 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:

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.

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.

How Much Exercise Is Enough?

“I’m a minimalist when it comes to exercise. A really small, really intense dose is all that is needed for the vast majority of people to manifest all of the health benefits that exercise can provide. This does not mean that you can then get away with bed rest in the face of this concentrated dose of exercise, I’m not saying that at all. I’m saying that if a person is living a fairly “normal” life with a decent amount of non-exercise activity built into their day, not a lot of “exercise” is needed above that to maximize health markers.”

     –Skyler Tanner in a recent blog post (click for the rest)