Nutrition Sports PET3361 Study Guide Exam II Know the legal limit for urinary caffeine concentration and how intake affects the measurement Caffeine is on the banned substance listed only if one has more than 15ug ml in their urine Optimal Intake would be 5 mg kg BW given approximately 30 min before exercise to help reduce fatigue So 12 16 cups would be banned Though when exercising the half life of caffeine can decrease drastically Effect of 6 hours at rest 3 hours exercising What are the performance benefits of caffeine consumption and the required dosage Enhances performance via the effect on the central nervous system fat mobility possible use of fat lipolysis and saves our stored CHO for later Not much benefit with strength power performance but benefit seen in endurance Recommended dosage 2 4 cups of coffee 200 400mg at one dose to have an effect Explain caffeine s mode of action Active compound is methylxanthine Adenosine inhibition Adenosine inhibits NE release Catecholamine When caffeine is around we have more Epinephrine secretion CNS stimulation Excitement in CNS jitters decreases pain with muscle contractions PDE Inhibit intracellular signaling of cAMP and thus caffeine can prolong the action of cAMP by stopping PDE and the production of exercise hindering byproducts i e feelings of pain are reduced Caffeine stops PDE and allows cAMP to continue on Good for LIPOLYSIS but doesn t burn more fat This allows us to save our CHO stores for later Explain green tea s mode of action No credible evidence exists to support claims that there are health benefits of green tea It is rich in plant compounds that may protect lab animals from diverse diseases but there is no final decision as to whether it protects humans against heart disease strokes cancer or cognitive decline Explain beta alanine s mode of action Beta alanine is an Amino Acid derivative and is naturally made in our liver Beta alanine increase LBM and carnosine concentrations within our skeletal muscle B alanine is the Rate Limiting Enzyme for Carnosine Carnosine is a buffer during high intensity exercise 1 Mode of Action Acts as a buffer during high intensity exercise with intramuscular H ion buffering This would Optimally we should take 3 6 g of B alanine day x 4 weeks Its best to split this up by taking a a delay our sense of fatigue 2x800 mg dose every 2 3 hours 3x day What does HMB stand for Hydroxy methylbutyric acid or hydroxy methylbutyrate Explain when buffering solutions may be appropriate and why What is the typically recommended dosing guideline Do they work Our bicarbonate buffering system provides a major line of defense against increased intracellular H concentration Maintaining high bicarbonate extracellularly rapidly releases Hydrogen from cells and delays the onset of intracellular acidosis This may result in enhanced anaerobic performance VO2 max training volume and LBM Ergogenic befits of pre exercise alkalosis occur significantly in both men and women Ideal is 3 5 g kg BW in a 5 L solution an hour or two prior to competition Why is EPO use both beneficial and potentially dangerous EPO is a chemical that stimulates RBC production Too many RBCs can lead to a thick and very viscous blood This is dangerous as clotting and potentially death can result EPO can increase our oxygen carrying capacity and VO2 max Explain the normal physiological status of creatine sources and function during exercise and recovery 95 of our creatine is stored in the muscles and the liver and kidney naturally produce it It can also be consumed from fish and beef There are 3 amino acids required to produce Creatine naturally Gly Ala Met Function during exercise To put off going into glycolysis and lower our lactate production This will improve exercise capacity and increases our muscle CXAs FFM This is great for sub 30 second exercise and doesn t have as many aerobic benefits Know the typical creatine supplementation dosing strategy its effect on total Cr and the resynthesis of PCr How does CHO influence supplementation 2 If we take Creatine with CHO we have a better surge of insulin to help drive the product into the muscle itself Loading phase 20g for 5 days Split dosing is now recommended What are the effects of creatine supplementation on performance in activities at different durations intensity dependent variable Has creatine been effective in longer duration activity Able to last a longer amount of time and increase training volume as lactate threshold was improved This provided significance in terms of strength gains Can also work in endurance athletes where LBM strength and sprint performance were improved How has Cr been shown to affect body composition There has been no change in Fat mass or Body Fat There has been change in improvements with FFM and Total body mass i e we are making muscle gains Does creatine shut down your kidney s Not necessarily this is mainly anecdotal and not proven evidence Though Creatine can cause GI distress and weight gain What affects do Andro stenedione and stenediol have on the body Androstenedione is a testosterone precursor When taken there was no effect on testosterone levels overall The levels can increase but once androstenedione is not taken testosterone levels will return to normal There is no real strength gain with this and HDL levels were lowered Too much can lead to conversion to Estradiol to Estrogen Know the possible mechanisms of HMB action As stated in lecture HMB is a byproduct of Leucine metabolism and thus is normally already in our bodies We typically produce 2 4 g HMB Day depending on Leucine intake HMB can stimulate HMG Co A reductase to increase substrate for muscle and cellular repair This could also decrease the ubiquitin pathway a pathway normally causing protein degradation so loss of protein is prevented HMB acts on the mTOR pathway to increase protein synthesis HMB enhances the repair of 3 our sarcolemma HMB is effective when training at an intense level and can inhibit proteolytic process Total body strength and FFM improve How do anabolic steroids work Anabolic steroids build up the muscle and inhibit androgen growth factors i e facial hair genital changes These mimic testosterone These steroids bind to T receptors enter the nucleus of the cell and bind to DNA to promote protein synthesis These inhibit and compete with cortisol We can increase our protein synthesis muscle mass speed and BMD Cholesterol is transformed to Pregnenolone via Cytochrome P450