Search results for "TONIC CONTRACTION"
showing 5 items of 5 documents
Characteristics of histamine tachyphylaxis in rat uterine smooth muscle.
2002
Objective and design: To study both the desensitisation induced by short-term exposure to histamine and the mechanism responsible in the isolated rat uterus.¶Material: Precontracted isolated uterus (37 mM KCl) from oestrogenised Wistar rats were used.¶Treatment: Repetitive responses to histamine (10–6, 10–5, 10–4, 10–3 M), dimaprit and clonidine (10–4 M) were tested at 15, 30, 45 and 105 min., with their modifications by (5 mg/ kg, 24 h before sacrifice) reserpine, 10–7 M propranolol, 10–8 M atropine, and 10–6 M indomethacin. Dose-response curves for adrenaline were carried out as standard protocol.¶Methods: In vitro techniques (de Jalon's solution, 31°C, carbogen, isotonic registration, re…
Gender variations of body composition, muscle strength and power output in morbid obesity
2005
BACKGROUND: Motor capabilities are reduced in obese (OB) individuals, and this impairment may result also from quantitative variation of muscle mass due to alterations in body composition. OBJECTIVE: This study aims to evaluate the differences in body mass (BM) and composition, as well as in muscle strength (ST) and power output W(.) between OB and NW males and females, and to test the hypothesis that variations in body composition affect muscle performance in OB subjects. DESIGN AND METHODS: Body composition (determined by BIA with a two-compartment model), upper and lower limb maximum ST (evaluated with isotonic machines) and lower limb maximum anaerobic W(.) (measured with a jumping test…
Body mass reduction markedly improves muscle performance and body composition in obese females aged 61-75 years: comparison between the effects exert…
2004
OBJECTIVE: To investigate the effectiveness of a body mass reduction programme entailing diet caloric restriction and moderate physical activity with or without supplementary treatment with recombinant (r) GH or steroids to improve body composition and muscle performance in severely obese women aged 61-75 years. METHODS: Twenty women were randomly assigned to one of three groups: body mass reduction alone; body mass reduction plus rGH; body mass reduction plus nandrolone undecanoate. Body composition, isotonic muscle strength and anaerobic power output during jumping were determined before and after the 3-week period. RESULTS: Whatever the experimental group considered, body mass (P<0.01…
Comparison of post-activation performance enhancement (PAPE) after isometric and isotonic exercise on vertical jump performance.
2021
Purpose This study aimed to compare the post-activation performance enhancement (PAPE) induced by isometric and isotonic exercise on vertical jump performance. Methods 18 healthy trained men (25.8±2.7 years; 78.4±8.2 kg; 175.7±6.1 cm; 25.4±1.8 BMI; 126.72±10.8 kg squat 1-RM) volunteered for this study. They randomly performed two different PAPE protocols: Isotonic squats (ISOTS), which consisted of 2 sets of 3 repetitions at 75% of one-maximum repetition (1-RM); and isometric squats (ISOMS), which consisted of 2 sets of 4 seconds of submaximal (75% of 1-RM) isometric contraction at 90°-knee flexion. Countermovement jump (CMJ) height was tested at baseline and 4 minutes after each condition…
Voltage- and Agonist-Induced Activation of Smooth Muscle of the Human Upper Urinary Tract: Different Mechanisms
1985
Smooth muscles are such a remarkably diverse group of tissues that the difference in properties between any two of them may be as great as between a smooth muscle and a striated muscle. With this diversity it is not surprising that the ways in which different stimuli initiate contraction are also extremely varied and interesting although we still know very little about the details of the mechanisms involved. In an attempt to shed some light on the cellular contraction cycle of smooth muscle of the human upper urinary tract, this article will focus on two topics: 1. Previous findings in smooth muscle research will be summarized and discussed briefly as they are pertinent to an understanding …