Search This Blog

Friday, January 29, 2010

High Intensity Aerobic Interval Training

In my posting of November 18, 2009, I mentioned some strong advantages to interval training. The type of interval training discussed involved cycling for 10 seconds at all-out intensity followed by 20 seconds of easy pedaling, repeating this 10 times. This 5-minute workout produced aerobic improvements similar to those of running steadily for 20-25 minutes and, in addition, produced improvements in max power output and in resistance to fatigue from repeated work bouts.

A different type of interval training is discussed in an article by Schoenfeld and Dawes in the Strength and Conditioning Journal (vol. 31, no. 6, December 2009). The High Intensity Aerobic Interval Training (HIIT) described involves work intervals of about 1 minute each, interspersed with recovery intervals (1 minute long for trained athletes and up to 4 minutes long for the less fit. The following program for the highly fit is included with the article.

Time (min)            Perceived Difficulty
                   (1-10 where 1= very easy, 10 = very difficult)
     3                              3 (warm-up)
     4                              5
     1                              7
     3                              5
     1                              8
     1                              5
     1                              9
     1                              5
     1                              9
     1                              5
     1                              9
     1                              5 
     1                              9
     2                              5
     1                              8
     3                              5
     1                              7
     3                              3 (cool-down)

The authors cite research evidence for the advantages of this type of training over steady-rate endurance training. They include greater improvements in maximal rate at which oxygen can be used to produce energy, blood-vessel wall health, blood pressure, insulin action, and reduction of body fat deposited under the skin.

CAUTION: No-one should engage in an exercise program without first determining whether a doctor's clearance is needed first. See our Exercise Risk Questionnaire. Even if you are cleared for general exercise, you may not be ready yet for interval training, which should only be undertaken by people who are already well-conditioned. It is an intense form of exercise that puts considerable strain on the heart, lungs, muscles, and bones. Running intervals can easily cause muscle pulls or other musculoskeletal injuries, so very thorough pre-interval warm-ups are necessary. Cycling and rowing intervals involve less impact and peak force on the musculoskeletal system than running and are thus less likely to produce injury. However, any interval training must be approached with caution. Overtraining can occur with excessive high-intensity training. Symptoms include fatigue, decline in performance, unexpected weight loss, poor sleep, fast pulse, and lack of motivation. The key points are to start with a well-conditioned individual, warm up very thoroughly, and start at a moderate level of difficulty, increasing the intensity of intervals over a period of several weeks.

Tuesday, January 26, 2010

Places Where People Live Long - What They Have In Common

Dan Buettner, in his book, "The Blue Zones: Lessons for Living Longer from the People Who've Lived the Longest" reveals the factors in common among cultures that have very long life expectancies. In his lecture, televised on CNN, he delves into the cultures of the highlands of Sardinia (which has the longest male life-expectancy), Okinawa (which has the longest female life-expectancy) and Seventh-Day Adventists (who have the longest life-expectancy in the U.S.). There are 9 factors that he states are common to all these societies:

Move Naturally
1) In these societies, people don't perform programmed exercise. They just exercise as part of their daily lives. Okinawans get up off the floor 40+ times a day. Sardinians walk and garden a lot. Seventh Day Adventists take nature walks regularly. The common denominator seems to be a large volume of low-level physical activity.

Right Outlook
2) Downshift daily: That means to take some time daily to calm down, meditate, contemplate, or pray.
3) Purpose now: Have a purpose in living, either work, taking care of others, creating something beautiful, etc.

Eating Wisely
4) Wine in moderation (although the 7th Day Adventists discourage alcohol consumption)
5) Plant-based diet: Meat may be consumed but in relatively small quantities.
6) 80% Full Rule: Stop eating when you feel 80% full.

7) Loved ones come first
8) Belong to supportive groups
9) Right Tribe: Associate with other people who have good living habits

Thursday, January 21, 2010

Strength Training Helps Seniors in Daily Living Activities

A study by Hanson et al., published in the Journal of Strength and Conditioning Research (vol 23, no 9, 2009) tested the effectiveness of strength training in improving the ability of elderly people to perform activities of daily living. 35 men and 65 women, all initially sedentary, were trained 3 times per week for 22 weeks on Keiser pneumatically-resisted machines. The first 10 weeks involved only knee extension training, but the routine for the final 12 weeks included knee-extension, chest press, seated row, seated leg curl, abdominal crunch, and alternating leg press. The subjects improved significantly in knee-extension strength and power, leg-press strength, and fat free mass. They also became significantly faster in functional activity tests such as a 20-foot walk, repetitive (5x) standing up from and sitting down on a chair, and getting up from a chair and walking 16 feet. Improvements in strength, power, and fat-free mass correlated positively with improvement in the functional activities. This study shows that resistance training can improve strength and power at any age and such changes lead to improvement in performance of daily life activities.

Wednesday, January 6, 2010

Balance Can Be Improved By Training

A review by DiStefano, Clark and Padua of the effectiveness of balance training was published in the Journal of Strength and Conditioning Research (vol 23, no 9, pp. 2718-2731, 2009). The article assessed the effects of training on the following 3 types of balance:

Static balance on a stable surface: For example, holding a stable body posture while standing on one leg on a flat floor.

Static balance on an unstable surface: For example, holding a stable body posture while ice-skating on one leg (the skate is the unstable surface).

Dynamic balance: For example, performing a dismount from a balance beam or high bar and landing stably; snow-boarding; skiiing.

Effective Exercise for Improving Each Type of Balance
The following training methods were shown effective for improving the various types of balance when performed at least 10 minutes per day, 3 days per week, for 4 weeks.

For static balance on a stable surface:
     Wobble board (a board with a cylindrical roller under it)
     Ankle disc (a board with a hemispheric ball attached to the underside)
     Balance sandal (with a hemispheric ball under the midsole)

For static balance on an unstable surface:
     Wobble board
     Foam pad
     Balance trampoline
     Tilting platform
     Jump to hold (dynamic)

For dynamic balance:
     Wobble board
     Foam pad
     Balance trampoline
     Single leg balance with contralateral limb and trunk motion
     Single leg balance with external perturbations

NOTE: The authors stated that effective balance programs started with comfortable, less challenging exercises (e.g. static, on two legs, on stable surface, eyes open) and progressed, according to the individual's ability, to more challenging exercises (dynamic, on one leg, on unstable surface, eyes closed).