If you are referring to how many pushups to do in one session, the short answer is as many as you can. Aim for a number that challenges you but is still realistic. Build up from day to day to increase muscle strength. If you are referring to how long you should do pushups as a form of exercise, that is up to you. Pushups are a good part of a long-term or permanent exercise regimen. Remember that if you stop doing them, your muscles will weaken.
Eat 0.4–0.5 grams of fat per pound of your body weight. Fat is essential for hormone optimization, brain function, and joint health. Now, if you’re following a ketogenic diet (or modified keto diet), or you just feel better with more fat in your diet, you can certainly add more fat and lower your protein and carb intake to accommodate it. The 0.4–0.5 grams per pound recommendation just represents a starting point and a minimum so that you don’t eat too little fat, either out of fear that it will make you fat or damage your heart (both untrue). For more about ketogenic diets, see Onnit’s guide HERE.
Creatine is only taken up by its transporter, and changes in the activity level of this transporter are wholly causative of changes in creatine uptake. The transporter is regulated by mostly cytosolic factors as well as some external factors that affect creatine transport activity,  including extracellular creatine. Agents affecting creatine transport are further divided into positive regulators (those that increase activity of the transporter) and negative regulators (those that suppress activity).
Creatine is normally metabolized into creatinine (note the difference in spelling), which is eliminated by the kidneys under normal conditions. When the kidneys fail and cannot clear the blood as effectively, many metabolites get “backlogged” in the blood. Creatinine is easy to measure and as such it is a biomarker of kidney damage. If serum creatinine levels are elevated, the doctor may suspect some kidney damage. Low-dose creatine (≤5 g/day) may not cause alterations in this biomarker in otherwise normal adults but high doses of supplemental creatine may cause a false positive (an increase in creatinine, due to creatine turning into creatinine, which does not signify kidney damage) and is a diagnostic error. Most studies, however, have noted only a small increase in creatinine levels even with doses ≈20 g/day.
The exercises that allow you to use the greatest amount of weight are the ones that help you build muscle the fastest. These also happen to be the lifts that allow for the greatest percentage of increases in loading. We’re talking compound (multi-joint) exercises here, done with free weights. You’re not going to grow at nearly the same rate with a workout comprising machine exercises and isolation movements.
Related to exercise and fitness, BCAAs are taken to help reduce muscle breakdown, which is why they may be known as muscle building supplements. Leucine, in particular, is known for playing an important role in muscle protein synthesis, which can help with muscle gain and maintenance. Some also claim that BCAAs can enhance performance, although many studies also refute this claim.
Moreover, the Food and Drug Administration (FDA) has identified numerous products marketed as bodybuilding or muscle-building dietary supplements that contain hidden active ingredients, including prescription drugs and steroid and steroid-like ingredients. Not only do these ingredients pose serious health risks, they might cause you to pop positive on a drug test. The only way to be sure a product contains only what’s on the label is to look for one that has been evaluated by an independent, third-party organization. For more information, visit FDA’s Consumer Update about bodybuilding products.
Caffeine is the naturally occurring alkaloid and stimulant in coffee, tea, cocoa, guarana, cola and other plant product beverages. A strong cup of brewed coffee will give you about 100 milligrams of caffeine, instant coffee around 80 milligrams, often less, and tea down around the 40 milligrams. It varies from product to product and how you prepare the drink.
If you're 12 weeks out from a competition, you want to maintain as much muscle as possible while torching fat from every angle. This means low-intensity cardio – high intensity cardio speeds up your metabolism and burns fat very quickly, so you run the risk of burning muscle too, Terry says – either first thing in the morning on an empty stomach, or immediately after your weights session, once you’ve depleted those glycogen levels.