- Muscle strength is directly proportional to muscle cross-sectional area and is affected by factors like muscle length, velocity of contraction, and the type of contraction (eccentric, concentric, isometric). - Common techniques to increase strength include progressive resistance exercise programs (DeLorme, Oxford) and exercising to muscle fatigue with both high and low weight. - Physical agent modalities like heat, cold, ultrasound, electrical stimulation and massage can be used to treat muscle and joint conditions. Precautions must be followed for each modality. - Manipulation techniques like mobilization, muscle energy and counterstrain are commonly used by physiotherapists to restore joint range of motion. Risks are generally

1. Physiatric Therapeutics

16. Physical Agent Modalities

17. Physiologic response to Heat Heat Decreased Blood viscosity Increased tissue temp Increased Local sweating Increased Phagocytosis Arteriolar Dilatation Increased Capillary Flow Increased Capillary Pressure Increased Capillary Permeability Increased Clearingof Metabolic waste Increased Supply of nutrients

40. CRYOTHERAPY Cold Decreased Tissue Temp. Increased Blood Viscosity And Vasoconstriction Decreased Metabolism Decreased Bleeding Decreased Removal of By Products Decreased Production of Metabolites Decreased Leucocyte Phagocyte Activity Retard Healing

49. Manipulation

60. Traction

65. Massage

83. Electrotherapy

85. Muscle Properties I IIa IIb Morphology Name Red Intermediate White Capillary density Intermediate Histochemical Myosin ATPase Mitochondria Glycogen Low Intermediate High Myosin HC HCs Hcfa HCfb Myosin LC LC 1a , 1b,2 Lcf 1,2,3 Lcf 1,2,3

86. Muscle Properties I IIa IIb Metabolism Type Oxidative Oxidative/ glycolytic Glycolytic Aerobic Mixed Anaerobic Contractile properties Twitch Slow Fast Fast Fatigability Slow Intermediate rapid