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:10/28/2014)... differences in moving activity in a novel environment ... angling, according to an experimental study completed at ... Game and Fisheries Research Institute. The study used ... and authentic angling trials to analyse if behaviours ... reared in traditional and enriched hatchery rearing environments. ...
(Date:10/28/2014)... and citrus fruits and juices are associated with a ... research from the University of East Anglia (UEA). ... foods containing flavonols and flavanones (both subclasses of dietary ... cancer, the fifth-leading cause of cancer death among women. ... of 171,940 women aged between 25 and 55 for ...
(Date:10/27/2014)... are an indigenous species of the West Antarctic Peninsula ... Earth. Since 1950, the average annual temperature in the ... and 6 degrees Celsius during winter. , As ... dry, polar system to a warmer, sub-polar system with ... a connection between local weather conditions and the weight ...
Breaking Biology News(10 mins):Fish 'personality' linked to vulnerability to angling 2Tea and citrus products could lower ovarian cancer risk, new UEA research finds 2University of Delaware study connects penguin chick weights to local weather conditions 2University of Delaware study connects penguin chick weights to local weather conditions 3
(Date:10/30/2014)... 2014 Spartan Bioscience announced today that ... System . It detects CYP2C19 genetic mutations in less ... The Spartan RX CYP2C19 System is the first near-patient ... in Canada. Due to the system’s ease of use, ... by healthcare professionals such as doctors, nurses, pharmacists, and ...
(Date:10/30/2014)... , Oct. 30, 2014 A new report, ... Partnership Practice, takes an in-depth look at ... that have resulted over two different time frames: 1993 ... a view of future opportunities for investment growth.  The ... report shows gains in innovation dollars as ...
(Date:10/27/2014)... October 27, 2014 The new ... Type (High & Medium), Sub-type (Primary & Secondary), ... Infrastructure & Transportation & Power Generation) - Trends ... GIS market with analysis and forecasting of the ... Data Tables with 52 Figures spread through 146 ...
(Date:10/27/2014)... MA (PRWEB) October 27, 2014 ... profit. SoundConnect , an industry leading unified ... its partners and agents to deliver cloud-based audio ... accelerate growth opportunities. , With SoundConnect’s Q4 ... every twenty-five video and/or web conferencing licenses sold, ...
Breaking Biology Technology:Health Canada approves first near-patient DNA test for personalized medicine 2Health Canada approves first near-patient DNA test for personalized medicine 3New report shows Indiana's gains in life sciences innovation capital outpace the nation 2New report shows Indiana's gains in life sciences innovation capital outpace the nation 3New report shows Indiana's gains in life sciences innovation capital outpace the nation 4New report shows Indiana's gains in life sciences innovation capital outpace the nation 5Gas Insulated Switchgear Market worth $21,951.9 Million by 2019 - New Report by MarketsandMarkets 2Gas Insulated Switchgear Market worth $21,951.9 Million by 2019 - New Report by MarketsandMarkets 3Gas Insulated Switchgear Market worth $21,951.9 Million by 2019 - New Report by MarketsandMarkets 4SoundConnect Unveils Q4 Partner Incentives 2
Cached News: