Nutrition for Muscle Development

Part II

Macronutrients

• Proteins: provide amino acids

• Carbohydrates: primary energy source

• Fats: maintains hormonal environment

Proteins

• Made of carbon, hydrogen, oxygen, and nitrogen

• Amino Acids: primary building blocks of protein

• 20 different types of A.A.– 9 essential– 11 nonessential

• Rated on biological value– Essential AA content– High = complete (usually animal sources)– Low = incomplete (plant based)

• Contain 4 Cal/gram– NOT primary

• Inefficient– High thermic, low energy density

How Muscle Uses Protein

• Increase training = increase synthesis/degradation– Synth>degrad = growth

• AA before and after exercise stimulates synthesis– Greatest anabolic effect when taken with carb

• During fasting: high protein can lead to increase lean body mass & stength

Daily Protein Requirements

• Some: 1.2 – 1.7 grams/kg body weight

• Others: 0.8 grams/kg body weight

• General Recommendations– 25-30% of daily caloric intake– Higher training may require more

– Essential more important than non-essentials

Carbohydrates

• Made of carbon, hydrogen, oxygen

• 4 Cal/gram– More efficient than protein

• Converted into glucose– Stored glycogen

• Stored in muscle and liver

• Major source of energy

How Muscle Uses Glycogen

• Glycogen glucose ATP

• Depletion may inhibit volume or intensity– Need adequate amounts

• Replace stores ASAP after training– Maximize insulin effects

Carb effects…

…on testosteroneprolongs decreased levelsPWO increases protein specific synthesis

-increased uptake into muscle?

…on cortisoldecrease responsereduce need for gluconeogenisis

Daily Carb Requirements

• General public 5-6 g/kg of body weight– 55-60% of caloric intake– Athletes may require more

• Glycemic Index– How quickly a carb is metabolized

• Highmetabolized quickly (fruits/processed sugar)• Lowmetabolized slowly (starches/cellulose)

– Glycemic Load= total of entire meal

Fats

• Composed of carbon, hydrogen, oxygen

• 9 Cal/gram 1 lb of fat = 3500 kcal– Most energy dense

The Good vs The Bad

• Bad saturated (animal) & trans (commercially packed food)– Elevate cholesterol

• Good mono-, polyunsaturated (veggies, nuts, and seeds)– Improve blood lipid profile

• Moderate amounts:– 15-20% of caloric intake (>10% saturated)

Water

• Body is 40-70% water– Essential for muscular growth– For every 1g of carb there is 2.7g water– Dehydration as little as 1.5% can decrease

performance

– Consume 8 (12 oz) glasses/day

Micronutrients

• Vitamins & Minerals– Body functions & biochemical reactions

• Vitamins – non-caloric, organic– Water soluble – B, C (not stored)– Fat soluble – A, D, E, K (stored in fat tissue)

• Small amounts

– Roles in energy metabolism & tissue formation

• Minerals inorganic substances (soil)– Macrominerals (35-1150 g/day)

• Calcium, phosphorus, magnesium, sulfur, sodium, potassium, chloride

– Micro (trace) minerals (less than a few grams)• Iron, iodine, fluoride, zinc, selenium, copper,

cobalt, chromium, manganese, molybdenum, arsenic, nickel, vanadium

• Deficiencies may impair strength training

Supplementation

• Creatine: derived from AA– Synthesized in liver, pancreas, & kidneys– Increase bioavailability of PCr for ATP

metabolism– May increase muscle contraction & delay

anaerobic fatigue– Amount varies– Supplementation:

• Strength progression in females• Enhance max strength & weightlifting performance

BCAAs

• Branched Chain Amino Acids– 3 essential AA

• Leucine, Iso-leucine, valine– Eggs, whey, meat, dairy

• Role in muscle metabolism

L-Carnitine

• Synthesized carnitine in liver & kidneys– Meats, dairy – Spares muscle glycogen

• Increase fatty acid oxidation

– Delay fatigue