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:7/23/2015)... , July 23, 2015 Research ... addition of the "Global Outlook of the ... offering. The global biometrics market ... public and commercial applications owing to the uptake ... witness a transformation that enhances the growth of ...
(Date:7/13/2015)... 13, 2015 Synaptics Inc. (NASDAQ: ... solutions, today announced sampling of ClearPad ® ... integration (TDDI) product targeting smartphones and tablets. This ... Synaptics , best-in-class touch controller IP and ... developed in the company,s Japan Design Center. TDDI ...
(Date:7/9/2015)... , July 9, 2015  Synaptics ... developer of human interface solutions, today announced ... industry,s first fully hardware encapsulated fingerprint sensor ... authentication technology is literally off the grid, ... biometric matching within the fingerprint sensor to ...
Breaking Biology News(10 mins):Global Outlook of the Biometrics Industry 2015 2Global Outlook of the Biometrics Industry 2015 3Synaptics Announces Sampling of Second Generation TDDI Solutions 2Synaptics Announces Sampling of Second Generation TDDI Solutions 3Synaptics Announces World's First Match-in-Sensor Fingerprint Authentication Technology 2Synaptics Announces World's First Match-in-Sensor Fingerprint Authentication Technology 3
(Date:7/29/2015)... ... July 29, 2015 , ... ... announced its GHS Label Guide . To align chemical container labeling with ... guide includes explanations of label components, an example of an accurate label, and ...
(Date:7/29/2015)... , July 29, 2015  Therapath Neuropathology ... announces increased partnerships with VA and Military Medical ... Nerve Fiber Density (ENFD) and Sweat Gland Nerve ... fiber neuropathy ( https://therapath.com/skin ). ... Fiber Density (ENFD) on punch skin biopsy is ...
(Date:7/29/2015)... SLOUGH, England , July 29, 2015  Indivior ... Application (NDA) for naloxone nasal spray was accepted and ... Administration (FDA) for the treatment of opioid overdose. This ... contains naloxone specially formulated for optimal absorption into the ... to require minimal training so individuals may be better ...
(Date:7/29/2015)... July 29, 2015 /PRNewswire/ - RepliCel Life Sciences Inc. ... medicine company, is pleased to announce that the final ... have been locked.  Prototypes for industrial and regulatory ... an application for CE mark clearance to market ... in 2016. (Photo: http://photos.prnewswire.com/prnh/20150729/248373 )  ...
Breaking Biology Technology:Brady Announces a New GHS Label Guide 2Neuropathology services for VA and Military health systems 2Indivior PLC Announces FDA Acceptance of Naloxone Nasal Spray New Drug Application With Priority Review 2Indivior PLC Announces FDA Acceptance of Naloxone Nasal Spray New Drug Application With Priority Review 3Indivior PLC Announces FDA Acceptance of Naloxone Nasal Spray New Drug Application With Priority Review 4Indivior PLC Announces FDA Acceptance of Naloxone Nasal Spray New Drug Application With Priority Review 5RepliCel Life Sciences Unveils Innovative Dermal Injector Prototype 2RepliCel Life Sciences Unveils Innovative Dermal Injector Prototype 3RepliCel Life Sciences Unveils Innovative Dermal Injector Prototype 4RepliCel Life Sciences Unveils Innovative Dermal Injector Prototype 5
Cached News: