HOME >> BIOLOGY >> NEWS
For the longest distance runner, that tired feeling may not be due to central fatigue

iology.

Methodology

Nine healthy male subjects (age 41.6 5.9 years; mass 152 15 lbs.; height 5 ft., 9 inches four inches; body fat 10.6 2.6 percent), all regular competitors in running or triathlon events, were enrolled in the study. The maximal twitches for knee extensors (KE) and plantar flexors (PF) were both examined before and after the 40-mile race using a bicycle ergometer. This testing device uses the inertia of a flywheel to provide resistance during both shortening (concentric) and lengthening (eccentric) muscle actions. This measures isometric, concentric, and eccentric muscle actions, assessing strength and velocity of different types of muscle actions.

The first session, when subjects were in a nonfatigued state, was conducted in the week prior to the ultramarathon. The test started with a 10 minute warm-up on the bicycle ergometer. The second session was undertaken in a fatigued state, two minutes after the race, and required 20 minutes on the bicycle ergometer.

During both sessions, the KE and PF were given electrical stimulation to determine muscle contractile measurements. During the test in the nonfatigued stage, the intensity was increased until there was no further increase in the height of the muscle twitch (involuntary contraction) or the amplitude of the M wave (electrically evoked muscle potential). The same stimulus level was used during the fatigued stage of the experiment.

Results

Maximal voluntary contractions and maximal voluntary activation decreased significantly after the ultramarathon (a decline of 30.2 18.0 percent and 27.7 13.0 percent, respectively). Surprisingly, peak twitch increased after the ultramarathon from 15.8 6.3 to 19.7 3.3 Nm) and from 131.9 21.2 to 157.1 35.9 Nm for KE. Also, shorter contraction and half-relaxation times were observed for both muscles. The compound muscle action potentials (M wave) were not significa
'"/>

Contact: Donna Krupa
djkrupa1@aol.com
703-527-7357
American Physiological Society
14-Mar-2002


Page: 1 2 3

Related biology news :

1. ICSI and IVF are safe results from worlds largest, longest running study
2. Yellowstones long-distance travelers in trouble, study says
3. Long-distance command sends human growth hormone into action
4. Action at a distance in the hyperoxic eye
5. Misfiring proteins tied to inflammation and sick feeling of type 2 diabetics
6. Scientists sequence genome of kind of organism central to biospheres carbon cycle
7. Genes may be central to cocaine addiction
8. Newborn lambs central heating system could aid fat busting in humans
9. Visualizing the central dogma
10. A link between thimerosal and the brain: Can vaccines affect central nervous system function?
11. Virginia Bioinformatics Institute central to Regional Center of Excellence

Post Your Comments:
(Date:7/28/2014)... team of researchers led by the University of Arizona ... The genetic information will enhance scientists, and agriculturalists, understanding ... as enable the development of new rice varieties that ... to help solve global hunger challenges. , The paper, ... ) and evidence for independent domestication," was published online ...
(Date:7/28/2014)... and organic compounds in hydrothermal environments are critical components ... for the deep biosphere, and may have implications for ... about how minerals influence organic reactions. A team ... a common mineral acts as a catalysts for specific ... solvents or expensive reagents. , At the heart of ...
(Date:7/28/2014)... Researchers at Yale School of Medicine have pinpointed a mechanism ... glucose levels in the blood, linking it to both type ... the July 28 issue of Proceedings of the National ... prolyl endopeptidase enzyme located in a part of the ... of steps in motion that control glucose levels in the ...
Breaking Biology News(10 mins):Generating a genome to feed the world: UA-led team sequences African rice 2Generating a genome to feed the world: UA-led team sequences African rice 3Generating a genome to feed the world: UA-led team sequences African rice 4Mineral magic? Common mineral capable of making and breaking bonds 2Mineral magic? Common mineral capable of making and breaking bonds 3Glucose 'control switch' in the brain key to both types of diabetes 2
(Date:7/28/2014)... Appistry, Inc. , a leading ... power of genomics to next-generation medicine, announced today its ... . , Two Appistry staff will be joined ... for Genome Resources, and Mr. Neil Miller, director of ... City. Rounding out the panel are Appistry’s Dr. Richard ...
(Date:7/28/2014)... The global market for biotechnology is expected ... a new study by Grand View Research, Inc. Increasing ... vaccines and drugs in an attempt to improve healthcare ... to drive market demand over the next six years. ... the use of genetically engineered seeds is expected to ...
(Date:7/28/2014)... and COLLEGE STATION, Texas , July 28, 2014 ... theatlashotel.com will be a 177-key, 4-star boutique hotel in the ... Bryan , Texas.  Photo - http://photos.prnewswire.com/prnh/20140725/130455 ... As the first hotel within ATLAS , ... a mixture of standard rooms and suites, a sleek restaurant and ...
(Date:7/28/2014)... IN (PRWEB) July 28, 2014 The ... Center, in Muncie IN, is pleased to announce that ... the National Museum of the United States Air Force. ... a year-long process that concluded this spring with an ... the Dayton, OH museum. , The National Museum ...
Breaking Biology Technology:Appistry Names Industry Experts from the National Center for Genome Resources and Mercy Children's, Kansas City, to Judge Pipeline Challenge Competition 2Global Biotechnology Market Worth $604.40 Billion by 2020: Grand View Research, Inc 2Global Biotechnology Market Worth $604.40 Billion by 2020: Grand View Research, Inc 3Global Biotechnology Market Worth $604.40 Billion by 2020: Grand View Research, Inc 4Texas' Biocorridor Announces the Atlas Hotel, Centerpiece of Mixed Use Community for Biotech Industry 2Texas' Biocorridor Announces the Atlas Hotel, Centerpiece of Mixed Use Community for Biotech Industry 3Texas' Biocorridor Announces the Atlas Hotel, Centerpiece of Mixed Use Community for Biotech Industry 4AMA’s National Model Aviation Museum Granted Full Civilian Museum Certification by the National Museum of the United States Air Force 2
Cached News: