Thursday, September 22, 2011

From NCSF newsletter.

Unfamiliar Loading

By: NCSF  on:  Sep 13 2011
The variety of movements in resistance exercise is limited to the normal safe biomechanics of the different joints. Essentially, a forward lunge is a forward lunge and a step-up is a step-up. Sure, angles may be adjusted but the movement is consistent. Diversity to the movement comes from loading, movement speed, stability, ROM and related stress adjustments to make the body do more while the movements remain safe and consistent. One way to get more from the training is to use unfamiliar loading. Traditional approaches commonly use axial loaded bar positions and lateral dumbbell holds. Thanks to the proliferation of training equipment, unfamiliar loading can add diversity, appropriate levels of difficulty and be more interesting to clients than the traditional redundancy. A very simple example of unfamiliar loading is applying resistance to a learned exercise in a different location. For instance, switching axial loaded forward lunges and lateral squats to front loaded with the bar. This simple movement of seven inches forward changes the stability requirements and weight distribution rather significantly. If triceps or lat tightness are issues, grab a sand bag or heavy bag for the same exercise.
Carrying and moving odd shaped objects improves the communication between muscle groups and enhances force couples and loading the front plays into the inefficiency of the spine. Carrying a dumbbell like a cradle (hooked arms) while performing step-ups or using a straight bar or plate instead of a medicine ball during lunges with rotation will change the exercise difficulty due to the unfamiliarity, assuming the loading is consistent. A longer resistance arm or change in the overall center of mass because an object is cumbersome makes it more difficult to move and control. The World’s Strongest Man competition demonstrates the use of unfamiliarity in many of the events. Logs replace bars, round and angular shaped stones require cradle carries, pulls use unfamiliar material like chains and thick ropes. This is not to suggest that clients should train to compete in these events but rather that utilizing different equipment or carry locations makes the training more interesting and much more functional than using machines and traditional axial loading. Consider some of the following adjustments in your exercise programs.
Cradled front carries with walking lunges (sand bags, heavy bags)
Front loaded Bulgarian squats (short barbell, dumbbell, sand bags, heavy med ball)
Side shouldered step-ups or stair climbs (water pail, sand bag, heavy bag)
Standing single arm bar press (grip plates, kettle bell, short bar)
Standing rotation (straight bar, grip logs)
Chin up (towel or rope)
If these sound a bit aggressive the variations can be more accommodating. Changing stances and pull positions create new stress even when the resistance is the same (or perhaps even lowered). If your client is accustomed to performing an exercise seated, have them perform it while standing. Each new experience creates a new perceived stress which, of course are the foundations for progressive adaptations. Changes may be directionally as well or use an increased movement range. For instance, if a forward step-up is the norm, switch to an angular step or if the step height is 15 inches, make it 18. Likewise, taking anchored actions and making them locomotive also changes the requirements of the exercise. Regardless of the decision just ensure proper instruction serves correct technique and biomechanics.

Heart Rates for Energy Expenditure
Weight loss is difficult. Not in theory – eat less and move more – but in implementation. One of the major obstacles for most people is the lack of knowledge and/or confusion surrounding caloric intake and expenditure. Most people consume more calories than they realize and burn far less calories than they expect. Knowing what (# of calories) is actually in the foods they consume is one problem and knowing how calories are referenced is another. A breakfast muffin for instance may have 400-600 kcal. While the label says 200 kcals/serving, some overlook that the label also states there are two servings per muffin. At quick glance the calories and fat presented are only half of the actual value. A similar problem occurs in the gym. The Stairclimber shows 300 kcal after a 30 minute workout. In reality, the value is only correct if the individual maintained an upright posture, did not lean on the machine, and maintained proper pace and range on the pedals; or more importantly sustained heart rates. Just like the serving and portion sizes matter in food, heart rate matters when performing continuous exercise aimed at achieving weight loss.
After 50% of VO2max, heart rates correlate increasingly well with VO2 at the same intensity. The chart below demonstrates the relationship between the percentage of measured heart rate and percentage of VO2max. The percentage of heart rate max is always charted on cardio machines and the general recommendation is to train between 75-90% of HRmax, or 60-80% of VO2max, which is explained by the number correlations below. The reason this is relevant is caloric expenditure is tied to oxygen utilization. If you know a person’s VO2 you can also determine an actual caloric expenditure by minute based on heart rates.
Percentage of HRmaxPercentage VO2max
Many fitness professionals have realized by now that the Elliptical Trainer and other static modalities do not predict energy expenditure accurately and based on usage dynamics commonly over-predict the caloric expenditure – giving clients a false sense of accomplishment and frustration at the lack of results at the same time. To correct this issue the first step is identifying how many calories a person can actually expend. Walk and run tests can do this with acceptable accuracy and present viable numbers to work with for weight loss. Below are two formulas for calculating the predicted VO2max and subsequent caloric expenditure potential. The one mile walk test best serves the less fit population, whereas the 1.5 mile run/jog test is designed for those in better shape. One caveat to both is the individual needs to perform at maximal effort and the distance must be accurate. Therefore, measuring the distance and practicing the test for pace is important for optimal validity.
One Mile Walk Test

VO2max (ml . kg-1 . min-1) = 132.853 - 0.0769(weight) - 0.3877(age) + 6.315(gender) - 3.2649(time) - 0.1565(HR)
  • Weight is in pounds
  • Age is in years
  • Gender = 0 for females and 1 for males
  • Time is in minutes and hundredths of minutes (ex. 13.51 = 13 minutes and 31 seconds) divide 31 seconds by 60 seconds
  • Heart rate is in beats per minute at completion (use a 10 sec count x 6)
1.5 Mile Run Test

The formula is not as complicated as it appears. Assume a 35 year old female weighing 138 lbs. ran the 1.5 mile in 12:13 min. The first thing that must be calculated is the average horizontal running velocity of the subject in meters per minute. To do this you must convert the distance run into meters and divide it by the number of minutes it took to complete the run.
Example Meter Conversion
1.5 miles = 2,413.8 meters
2,413.8 must then be divided by the time it took to complete the run in minutes (use whole numbers)
Example (m • min-1) conversion
If it took 12:00 minutes to complete the run, then 2,413.8 m / 12min = 201.15 m • min-1 (horizontal velocity)
If it took 12:13 to complete the run then the divisor would be 12.21 (12 +13/60))
Perform your conversion below:
2,413.8 meters ÷ 12.21 minutes = 198 m • min-1 (horizontal velocity)
VO2max conversion. The last calculation that must be performed is the one that will provide you with the subject’s estimated VO2max. Consider the above example:
Less scientifically written as (198 x.2) + 3.5 = VO2
VO2 max = 43.1
Now at 43.5 ml • kg-1 • min-1 the maximum oxygen use has been determined. A couple of multiplication equations later and the female’s maximal oxygen consumption expressed in calories is 810 kcal/hour. So if she was able to train at 100% of her VO2 she would be able to burn over 800 kcal/hour or 13.5 kcal/min (810 kcal ÷ 60 min). Some boot camps advertise that the class allows one to burn more than 1,000 kcal/hour - obviously an extreme exaggeration. So…assuming your client was going to train at a fitness level between 60-80% you can deduce the calories per minute accurately. Look at the example once again.
She burns 810 kcal at 100%. Which means at 60% (810 x .6) she burns 486 kcal/hour or 8 kcal/minute. At 80% she would burn 648 kcal/hour or 10.8 kcal/minute. These numbers are much more reasonable when it comes to predicting exercise related weight loss and also helps explain why it takes so long. Based on these facts if she exercised aerobically for 20 minutes at 60% of her oxygen capacity she would burn only 160 kcals (20 min x 8 kcal) or at 80% she would jump to 216 kcals; hardly enough to burn off the muffin. In fact, she would actually need about 40-45 minutes to burn off that breakfast muffin making it probably not worth the taste enjoyment.
Since not everyone is efficient with METs and not every machine has MET level buttons on them, it makes more sense to use Heart Rates. But, if you do use METs it is as simple as multiplying the VO2max times your training percentage and dividing by 3.5.
Example 43.1 ml • kg-1 • min-1 x 60% = 25.86 ÷ 3.5 ml • kg-1 • min-1 = 7.3 METs
43.1 ml • kg-1 • min-1 x 80% = 34.48 ÷ 3.5 ml • kg-1 • min-1 = 9.85 METs
Utilizing the MET intensity button for better accuracy helps, but if you’re more comfortable with Heart Rates use the Karvonen formula to establish the training zones as they correlate well with VO2 and subsequently with the calories expended. Here we simply measure the female’s resting heart rate. Let’s say it is 65 beats/min. We then calculate the max heart rate 208 – (.7 x age) and since she is 35 we get 184 beats/min. Subtracting the resting from the maximal heart rate gives us the zone to work in called the heart rate reserve which should make sense since we cannot exceed max nor go below rest – so we train somewhere in the middle. When completing the calculation for the actual training zone, we’ll need to add back in the resting heart rate to our calculated percentage of heart rate reserve. See example below:
183 bpm max - 65 bpm resting = 122 HRR
122 HRR x 60% + 65 bpm = 138 bpm
122 HRR x 80% + 65 bpm = 162 bpm
Based on the correlations and assumptions above if the female client gets her heart rate to 138 beats/min or works at 7.3 METs she will burn approximately 8 kcal/minute and if she gets her heart rate up to 162 beats min or 9.85 METs she will burn about 10.8 calories/minute. These values can be determined for any percentage over 50% VO2max or 70% HRmax by simply swapping out the training intensity. The reason this is such an effective method to determine caloric expenditure is there is no way to cheat. Either you are using the oxygen as monitored by your heart rate or you are not. This forces people to be more accountable for their effort and clearly identifies when they are not doing enough to create a negative caloric balance.

Fruit Comparison
Although some diet books and self proclaimed experts denounce fruits for their sugar content, the reality is fruit is an important dietary constituent. Fruits carry a diversity of nutritional elements and supply fiber, antioxidants and water to the diet. The calories per serving have extremely limited impact on daily caloric intake and the sweetness can be a viable option to many processed food snack choices. Most people who consume fruit have a few selections that they are familiar with and eat with some regularity but possible selections are quite abundant.
The apple, orange, and banana are well-known constituents likely followed by the more common commercial fruits including watermelon, pineapple, cantaloupe, and honey dew. Although any fruit is a good choice, eating a variety of fruits in one’s diet is what brings about nutrient balance. One way to experience dietary variety and assure the optimal flavor is to follow the fruit seasons. Since fruit in season is much more abundant and therefore cheaper and fresher it would be prudent to use this metric as a guide for shopping and eating. Secondly, each fruit contains a varying amount of each nutrient, so an additional strategy revolves around the combination of certain fruits to optimize nutrient intakes. Below is a chart that may aid in ensuring daily fruit intake reflects seasonal and balanced selections.
FruitServingSeasonCaloriesGI avgCarotenoids**Vit C.*Potassium*Fiber*
Watermelon2 cupsSummer9072HighHMLML
Red Grapefruit½Winter5025HighHMLML
Papaya½Year Round6059Mod-HighHMM
Cantaloupe¼Year round5065HighHML
Apricots¼ cupSpring7057HighMHMM
Blackberries1 cupSummer80N/AN/AHMLMH
Raspberries1 cupSummer60N/AN/AHMLMH
Honeydew1/10Year round5065ModHML
Blueberries1 cupSummer8053N/AMHLM
Banana1Year round12050N/AMMM
Cherries1 cupSummer10022N/AMMLM
Grapes1 ½ cupsFall10048N/AMHMLM
Pineapple2 slicesSpring6058N/AMHLML
* Approximate percentage of DV per serving
(H = >41% MH = 21-40% M = 10-20% ML = 5-9% L=<5%)
**CSPI Estimate - percentage < (5000 µg)
Source: USDA Nutrient Database for Standards Reference

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