Wave-like variations in muscular fatigue curves / by C.T. Symons.
- Symons, C. T.
- Date:
- [1908?]
Licence: Public Domain Mark
Credit: Wave-like variations in muscular fatigue curves / by C.T. Symons. Source: Wellcome Collection.
3/20
Licence: Public Domain Mark
Credit: Wave-like variations in muscular fatigue curves / by C.T. Symons. Source: Wellcome Collection.
![[Reprinted from the Journal of Physiology. Vol. XXXVI. No. 6, 1908.] WAVE-LIKE VARIATIONS IN MUSCULAR FATIGUE CURVES. By C. T. SYMONS, B.A. (Oxon.). (From the Wellcome Physiological Research Laboratoi'ies.) From time to time there have been noticed in muscular fatigue curves certain oscillations of the summit line, for which no definite reason could be assigned. The present work was undertaken in conse¬ quence of the accidental discovery of a means by which such oscillations could be produced at will. When the work had been practically completed it was noticed that Robert Muller1, following Wedenski, had observed certain variations, somewhat similar to the present ones, in frogs’ muscle fatigue curves, when short periods of tetanus were used. No other reference has been found in the literature on the subject to any similar phenomenon in fatigue curves. Method. In most cases the gastrocnemius muscle of the frog was used. The animal was pithed. A pin was passed through the knee- joint and formed one of the electrodes, and also served to fix the muscle to the frog-board. The other electrode consisted of a very fine flexible copper wire, sewn through the tendo Achillis ; this gave perfect freedom of movement to the lower end of the muscle. A thread was tied to the tendon, and passed round the larger wheel of a vulcanite pulley lever; the weight was hung on a smaller wheel on the same axle. In this way the tension on the muscle was very approximately constant at each stage of the contraction and relaxation. If the muscle was to be treated as isolated, the femur and overlying muscles were cut through and the tibio-fibula also severed a short distance below the knee-joint, leaving the gastrocnemius muscle alone covered with a “ trouser ” of skin. If the muscle was to be left in the “ circulation,” the foot was fastened by passing a pin through it into the frog-board. The lever was not supported, and usually the whole tension on the muscle, including Pli. xxxvi. 1 Robert Muller. Pfliiger's Arch. cvn. p. 297. 25](https://iiif.wellcomecollection.org/image/b30612986_0003.jp2/full/800%2C/0/default.jpg)
