Featured Research

from universities, journals, and other organizations

Some Muscles Respond To Weight Training In Just Two Weeks

Date:
July 28, 1998
Source:
Ohio University
Summary:
If you've just begun a weight training program and are discouraged by the lack of a bulging biceps, take heart: Even though changes aren't visible in a mirror, researchers at Ohio University and Pennsylvania State University have found the changes are visible under a microscope.

ATHENS, Ohio -- If you've just begun a weight training program and are discouraged by the lack of a bulging biceps, take heart: Even though changes aren't visible in a mirror, researchers at Ohio University and Pennsylvania State University have found the changes are visible under a microscope.

Related Articles


Exercise physiologists at the two institutions have found that molecular changes in the muscle begin within two to four weeks of initiating resistance training, far earlier than previously thought. What's more, the muscles appear to respond to even limited weight training. Scientists found significant changes in the thigh muscles after just four workouts.

"When most people begin a training program, they want to see immediate changes," said Robert Staron, associate professor of anatomy at Ohio University and co-author of this new study. "Our study suggests there are changes happening within the muscle which take place within a relatively short amount of time, even if they're not outwardly visible."

The activities the researchers monitored -- changes in hormone production and protein expression -- precede the increase in muscle mass longed for by beginning exercise enthusiasts.

"In the early phase of weight training, the body is adjusting its various systems to prepare you to become a stronger and more capable organism and it's these changes that we've found are happening at a much faster pace than anyone thought," said William Kraemer, professor of applied physiology at Pennsylvania State University and co-author of the study.

Thirty-three Ohio University students were recruited for the study. None were involved in a resistance training program at the onset of the project. Participants met with researchers five times every two weeks; four sessions were spent on weight training for the lower body and one was spent on strength testing for the lower body.

Resistance training focused on the quadriceps. Although the sessions lasted about two hours each week, the muscles actually were working only about 30 minutes a week, Staron said.

When they compared blood and tissue samples taken before training with those taken every two weeks during the eight-week program, researchers saw changes in production of testosterone, growth hormone and other chemicals as well as changes in the expression of myosin, the most common protein in muscles.

"There's a hormonal milieu that's bathing the muscle and it has a dramatic effect on the growth of the muscle," Staron said.

Women produce more growth hormone than men and the exercise program didn't seem to change that, Staron said. But the researchers did see startling differences between the testosterone response to exercise in men and women. Researchers suspect testosterone plays a role in muscle growth, but determining this is difficult. In this study, resistance training caused testosterone levels to increase significantly in both men and women when measured before, immediately following and five minutes after a workout.

However, the testosterone changes in the women were more dramatic compared to the men: Female participants saw a doubling in their testosterone levels. What's more, researchers recorded significant changes in the production of sex-hormone binding globulin (SHBG), a protein that binds with testosterone, helping transport it though the blood to the muscle cell.

"One possibility is that, in the women, SHBG is more active to protect what little bit of testosterone is produced during exercise," Kraemer said. "But it's likely that all of these hormones are involved with the repair process for the muscles, which are under stress at the beginning of a resistance training program."

This repair process makes the muscles more resistant to further injury and more responsive to the benefits of resistance training, Staron said.

"The muscle is a very adaptable tissue," he said. "The fact that we see these responses so early in training that only focused on one muscle group suggests that a whole-body workout might produce an even greater hormonal response."

The study is one of several resulting from a longtime collaboration between exercise physiologists at Ohio University and Kraemer, who in August will start a new position as professor and director of the Human Performance Laboratory at Ball State University.

The research was published in the June issue of the European Journal of Applied Physiology and was funded in part by the Ohio Board of Regents Research Challenge Program, Ohio University's College of Osteopathic Medicine and the Robert F. and Sandra M. Leitzinger Research Fund in Sports Medicine at Pennsylvania State University.

In addition to Staron, Ohio University co-authors include Fredrick Hagerman, professor of physiology, and Robert Hikida, professor of anatomy, all in the College of Osteopathic Medicine. Other authors were Andrew Fry, Scott Gordon, Bradley Nindl, Lincoln Gothshalk, Jeff Volek and James Marx, all from Pennsylvania State University; Robert Newton from Southern Cross University in Australia; and Keijo Hakkinen from the University of Jyvaskyla in Finland.

- 30 -

Contact: Robert Staron, (740) 593-2409; [email protected]

Written by Kelli Whitlock, (740) 593-0383; [email protected]


Story Source:

The above story is based on materials provided by Ohio University. Note: Materials may be edited for content and length.


Cite This Page:

Ohio University. "Some Muscles Respond To Weight Training In Just Two Weeks." ScienceDaily. ScienceDaily, 28 July 1998. <www.sciencedaily.com/releases/1998/07/980728081740.htm>.
Ohio University. (1998, July 28). Some Muscles Respond To Weight Training In Just Two Weeks. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/1998/07/980728081740.htm
Ohio University. "Some Muscles Respond To Weight Training In Just Two Weeks." ScienceDaily. www.sciencedaily.com/releases/1998/07/980728081740.htm (accessed November 24, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Monday, November 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Winter Can Cause Depression — Here's How To Combat It

Winter Can Cause Depression — Here's How To Combat It

Newsy (Nov. 23, 2014) Millions of American suffer from seasonal depression every year. It can lead to adverse health effects, but there are ways to ease symptoms. Video provided by Newsy
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Don't Fall For Flu Shot Myths

Don't Fall For Flu Shot Myths

Newsy (Nov. 23, 2014) Misconceptions abound when it comes to your annual flu shot. Medical experts say most people older than 6 months should get the shot. Video provided by Newsy
Powered by NewsLook.com
WFP: Ebola Risks Heightened Among Women Throughout Africa

WFP: Ebola Risks Heightened Among Women Throughout Africa

AFP (Nov. 21, 2014) Having children has always been a frightening prospect in Sierra Leone, the world's most dangerous place to give birth, but Ebola has presented an alarming new threat for expectant mothers. Duration: 00:37 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins