7 resultados para contracting
em Brock University, Canada
Resumo:
This study investigated the regulation of carbohydrate metabolism through changes in skeletal muscle cell volume immediately post contraction and during recovery. Using an established in vitro isolated muscle strip model, soleus (SOL) and extensor digitorum longus (EDL) were dissected from male rats and incubated in an organ bath (perfused with 95% O2; 5% CO2, pH 7.4, temperature 25°C) containing medium- 199 altered to a target osmotic condition (iso-, hypo- or hyper-osmotic; 290, 1 80, 400 mmol/kg). Muscles were stimulated for 10 minutes (40 Hz SOL; 30 Hz EDL) and then either immediately flash frozen or allowed to recover for 20 minutes before subsequent metabolite and enzyme analysis. Results demonstrated a relative water decrease in HYPER vs. HYPOosmotic condition (n=8/group; p<0.05) regardless of muscle type. Specifically, the SOL HYPER condition had elevated metabolite concentrations after 10 minutes of stimulation in comparison to both HYPO and ISO (p<0.05), while EDL muscle did not show any significant difTerences between the HYPER or HYPO conditions. After 20 minutes of recovery, metabolic changes occurred in both SOL and EDL with the SOL HYPER condition showing greater relative changes in metabolite concentrations versus HYPO. The results of the current study have demonstrated that osmotic imbalance induces metabolic change within the skeletal muscle cell and muscle type may influence the mechanisms utilized for cell volume regulation.
Resumo:
Receipt from George Wilson, Contractor and Builder, St. Catharines for contracting work, Sept. 30, 1887.
Resumo:
The Active Isolated Stretching (AIS) technique proposes that by contracting a muscle (agonist) the opposite muscle (antagonist) will relax through reciprocal inhibition and lengthen without increasing muscle tension (Mattes, 2000). The clinical effectiveness of AIS has been reported but its mechanism of action has not been investigated at the tissue level. Proposed mechanisms for increased range of motion (ROM) include mechanical or neural changes, or an increased stretch tolerance. The purpose of the study was to investigate changes in mechanical properties, i.e. stiffness, of skeletal muscle in response to acute and long-term AIS stretching for the hamstring muscle group. Recreationally active university-aged students (female n=8, male n=2) classified as having tight hamstrings, by a knee extension test, volunteered for the study. All stretch procedures were performed on the right leg, with the left leg serving as a control. Each subject was assessed twice: at an initial session and after completing a 6-week AIS hamstring stretch training program. For both test sessions active knee extension (ROM) to a position of "light irritation", passive resisted torque and stiffness were determined before and after completion of the AIS technique (2x10 reps). Data were collected using a Biodex System 3 Pro (Biodex Medical Systems, NY, USA) isokinetic dynamometer. Surface electromyography (EMG) was used to monitor vastus lateralis (VL) and hamstring muscle activity during the stretching movements. Between test sessions, 2x10 reps of the AIS bent knee hamstring stretch were performed daily for 6-weeks.
Resumo:
John Smith (1894-1977), son of Daniel Smith and Annie Douglas was a native of Scotland, immigrating to Canada in 1913. He first worked as a coach builder, then as a carpenter, finally developing his own contracting business. During WWI he served overseas with the 10th Battery, RCA as a sergeant. In 1924 Smith married Jean Wood, and together they had a daughter Irene (Hugh Langley). Smith first entered politics in 1940 serving as an alderman for the next 11 years. In 1954 he was elected mayor of the city of St. Catharines, and was twice returned to office by acclamation, serving until 1957 when he successfully ran as the Progressive Conservative candidate representing Lincoln County in the federal election. He won the election by a 10 000 vote majority. He served his constituents in Ottawa until he was defeated in the 1962 election. After leaving politics Mr. Smith was active in his community. He spearheaded the establishment of the St. Catharines Museum, and then was appointed its first director in 1966, serving in that capacity until 1972. He was an active member of the board of governors of the St. Catharines General Hospital and a life member and former president of the Lincoln County Humane Society. In 1971 he was voted Citizen of the Year for the city of St. Catharines. John Smith died on February 8, 1977 and was buried at Victoria Lawn Cemetery. Source: The St. Catharines Standard, February 9, 1977, page 1
Resumo:
This qualitative case study explored how the structural power imbalance in high performance sport influenced the bargaining process and resulting commercial rights and obligations of a single Canadian national sport organization’s (NSO1) Athlete Agreement. Principles comprising the doctrine of unconscionability, specifically the identification of a power imbalance between contracting parties, and the exploration of how that power imbalance influenced the terms of the contract, provided a framework to analyze factors influencing the commercial contents of NSO1’s Athlete Agreement. The results of this analysis revealed that despite the overarching influence of the inherent structural power imbalance on all aspects of NSO1 and its membership, an athletes’ level of commercial appeal can reach such heights as to balance the bargaining positions of both parties and subsequently influence the commercial contents of the Athlete Agreement.