Copyright 1997-2007  American Society of Exercise Physiologists. All Rights Reserved.



February 2007
Vol. 11 No. 2   
 Editor: Dr. Lonnie Lowery

Free ASEP-Newsletter email updates

  What's New:



  JEPonline       Ask the Professor  

  PEPonline       Why join ASEP?  



NOTE: The annual meeting will take place between March 29 and April 1 in Milwaukee Wisconsin!

Editorial: ASEP-Newsletter, Then and Now
Lonnie Lowery, PhD, ASEP Board of Directors

With 2007 underway, perhaps it is worth a recap of where the ASEP-Newsletter has been and where it is headed. This Newsletter began, in its present iteration, about five years ago at ASEP's National Summit on Licensure in 2002. That was the same year that I became involved in the cause, the organization and the Newsletter itself. With a large part of ASEP's mission being related to the graduated, practicing exercise physiologist (EP), we needed a means by which former students in the field could stay abreast of their profession and feel less isolated and forgotten. We also were in need of a vehicle by which EP faculty could receive news and updates from the organization that they knew held their students' best interests in high regard. Not everyone has the time to search through a web site regularly, so a friendly reminder in the "Inbox" of EPs everywhere was suggested. Tommy Boone gave me the opportunity to translate the existing ASEP-Newsletter of the time into an opt-in email format.

Although by no means new or inaugural (notice we are in Volume 11 this year), the email-focused ASEP-Newsletter began with 12 recipients - mostly the Board of Directors at the time. Since then it has changed colors from its original red, white and blue (plus a little black), added monthly columns, served as a platform for subscriber/ EP questionnaires regarding the profession, greatly expanded its advertisements of EP-related positions and products, kept a much wider audience aware of the ASEP National Meeting and Conference, and ultimately grown into a list of hundreds of monthly subscribers.

Today the members of the Board of Directors all contribute their knowledge, opinions, news and reviews to the ASEPNewsletter. The ASEP Journals, Journal of Exercise Physiologyonline and Professionalization of Exercise Physiologyonline offer free highlighted articles. A doctoral student in the field assists with the Ask the Professor column. Tommy Boone sends monthly ads from interested employers. An updated and enhanced web site integrates smoothly with it, largely thanks to Jesse Pittsley. Students publish material within it. Thanks to BOD member Matt Lehn, a total mailing list of thousands is reachable when an ASEP national event calls for it. There is much going on these days.

So although there is attrition on the mailing list each month due to bounces, the balance continues to lean toward growth. There is enough subscriber growth to justify, in my mind, the efforts that so many dedicated EPs put forth to make this Newsletter a reality. Thank you all.      

Go to top of page

Ask the Professor: Your Inside Scoop on Tough Questions
Note: Ask the Professor is intended for informational purposes only. It is not to be taken as healthcare advice. Please do not submit questions of a personal nature (e.g. fitness programs, nutrition advice solicitation, etc.) Thanks.

Question: What is meant by the term economy of movement? Can you explain the role of muscle mass, body composition, and choice of exercise mode/training? How does this relate to Sub-Max VO2 and how/why ones economy might get worse as one approaches their VO2max, as well as other factors potentially involved?  

Answer:  Whew! That's a lot. Movement economy refers to the energy required to maintain a constant speed of movement. This can also be used interchangeably with exercise efficiency. For example, a highly elite runner will exhibit better running economy than an untrained runner and will have a lower VO2 at any given running speed. The untrained or poor runner with less developed running economy will have a higher VO2 at any given speed, so therefore the untrained person is expending more energy to maintain the same speed as the elite athlete, if they are matched according to gender, height, weight, muscle, etc. However, this should be taken as a general rule of thumb. Other factors considering running economy/efficiency are respiratory capacity, body composition, training status, ventilation, power output, and steady state performance.

Muscle Mass/Body Composition also has an effect on economy of movement. Typically, a person with higher body mass/muscle mass will experience greater energy expenditure for a certain speed. For example, walking 3.0 mph and weighing 120 lbs will expend 3.6 cal/min, which results in 216 kcal in an hour. Therefore, a high speed results with greater energy expenditure, especially with a higher body masses. However, as previously mentioned, this is related with his/her exercise efficiency, which is influenced by several factors such as work rate, speed of movement, and fiber composition.

Exercise mode and training are also important factors in this equation. For example, efficiency of walking is slightly greater than cycling, although both respond similar to increments in speed and resistance. It is easier to cycle from one place to another than walking because rolling and wind resistance to cycling a certain speed is far less than accelerating and decelerating the body during walking. As a result, less work is done in cycling, especially if a person is highly trained and has greater pedaling economy.

Economy relates to Sub-Max
VO2 in several ways. As mentioned before, poor running economy exhibits a higher VO2 at any given speed, as opposed to the economical runner. Although running efficiency has not been shown to be a good predictor of performance, and is still not well understood, a high exercise efficiency can improve exercise performance because he/she are able to generate a greater power output at any rate of energy expenditure (amount of ATP used). Efficient runners are thought to have low vertical components in their technique, which has an effect on wind resistance. In terms of economy/efficiency, why might VO2 get worse as he/she approaches their max? Lets consider the following:

Exercise efficiency can be influenced by work rate, speed of movement, and fiber composition. For example, as work rate increases, total body energy expenditure increases in proportion to workload, which causes a decrease in efficiency. With speed of movement, research indicates an optimum speed of movement for any given work rate. So, as speed of movement increases, so does power output, in order to maintain optimum efficiency. Therefore, a decrease or increase in speed causes efficiency to go down.

Lastly, fiber type is also closely related. Individuals that contain a high % of slow twitch fibers have higher efficiency than individuals with a high % of fast fibers. Possible explanations include slow twitch fibers require less energy (ATP) per unit work than fast twitch muscle fibers. Other factors include resistance to fatigue, advanced cardio-respiratory capacity, oxidative enzymes, bioenergetics, and well developed buffering capabilities.


 Go to top of page

ASEP offers a new web page that you should see: "Why Join ASEP?" (just click the link then tell a friend!)
Don't forget to get on the free ASEP email list!

ASEP Contact Information
Please use this web page (click above) and new email address

ASEP is a member of the Health Profession Network
Check out the
HPN Links!

And keep in mind: For more information on professional scope of practice, professional standards and code of ethics for exercise physiologists, accreditation of academic programs, board certification examination, and other important tasks already completed by ASEP in establishing a profession, visit:

Go to top of page

Copyright ©1997-2007 American Society of Exercise Physiologists. All Rights Reserved.  All materials posted on this site are subject to copyrights owned by the American Society of Exercise Physiologists (ASEP). Any reproduction, retransmission, or republication (in whole or in part) of any document or information found on this site is expressly prohibited, unless otherwise agreed to by ASEP and expressly granted in writing to consent to reproduce, retransmit, or republish the material. All other rights reserved.