Unfortunately for any humanoid hoping to observe healthy gains in muscle mass, the vast majority of recreational drugs inhibit production of cellular components critical to androgenic activity. Opiates, benzodiazepines, stimulants, alcohol - all of these represent hurdles to reaping the benefits of time spent in exertion.
If we were to operate solely upon stereotypes, one would expect a drug-user/weight-lifter to be just about as dumb & dull as a box of rocks. Quite the contrary! Examples of such individuals observing gains in mass must be acutely aware of a tremendously wide array of cellular cascades - from muscular respiration to androgen/estrogen regulation. Below are some tips that the chimp's been using to his advantage for a while now:
The Valsalva Maneuver (VM): this is a method of breathing that yields maximal carbon dioxide removal from muscular tissues, which has recently been suggested to be the true limiting factor in maximal contracting force (rather than oxygen availability). During expiration, while employing the VM, increased respiratory-related neuronal activity synchronizes with motor-cortex impulses to non-respiratory muscles - thereby generating a greater aggregate signals at end-plate potentials, and therefore, stronger contractions. After performing brief maximum voluntary isometric contractions of large muscle groups (knee flexion & extension, elbow flexion & extension, shoulder abduction and adduction) during 4 different breathing conditions - the peak force produced in isometric muscular contraction in several subjects participating in a study was evaluated over 4 different breathing conditions. After a battery of statistical analyses, the research team confidently demonstrates that voluntary breathing indeed influences maximal muscle strength of large upper and lower extremity muscles. Unfortunately, the VM induces deletarious hemodynamic effects upon the cardiovascular system - raising blood pressure, heart rate, and the risk of cerebral hemorrhage. So while this isn't recommended for hypertrophy training, it can help to prolong time prior to muscular failure during maintenance or toning periods.
A good breathing pattern than proffers similar benefits to the VM, indeed safe for hypertrophy training, is quite simple. Instead of holding the breath while progressing towards the maximal moment of contraction - breath outward, so once maximal contraction is achieved, the lungs are emptied of air. This allows for enhanced carbon dioxide elimination, and may even abide by similar dynamics characterizing the forced-expiration of the VM.
Stretching by Reciprocal Innervation (RI): A major challenge posed to weight-lifters is the maintenance of a nimble range-of-motion. Generally speaking, this is due to persistent contraction of muscle fibers with little or no effective stretching to facilitate a return to initial elasticity. Over time, it becomes increasingly difficult to regain such flexibility - and therefore, chimps'd do well to stretch effectively before and after lifting.
At the level of the muscle, there are stretch receptors that are literally activated by the change in conformation at muscle fibers upon stretching. Upon activation, the receptors generate stimulations of muscle tissues to initiate contractions. This system exists to reduce the potential for hyper-extension and injury to muscle tissues - but can also serve to limit the efficiency characterizing stretching exercises. In other words, activation of stretch receptors when trying to stretch a warmed-up muscle for exercise will limit one's ability to stretch effectively.
Any muscle contraction is a function of a primary agonist, antagonist, and stabilizer muscles. To take a standing bicep curl as an example: the bicep is the agonist, tricep the antagonist, and leg/back/torso muscles are stabilizers. Agonist and antagonist muscles are reciprocally innervated; when an agonist muscle contracts, its antagonist must relax to permit the joint to contract. Accordingly, when a bicep is contracted, the tricep relaxes entirely. The reverse is true when the tricep is contracted - the bicep relaxes entirely. Partly, this is attributable to complete inactivation of stretch receptors in the relaxed antagonist muscle. This is the principle behind RI, as this inactivation in the antagonist persists for short periods of time subsequent to a contraction.
How to use RI: maximally contract the antagonist muscle of whatever muscle is to be stretched, isometrically, for at least 30 seconds (or until failure). Lets say we want to stretch the tricep. You can sit on a bench, and try to lift it while sitting on it (arm on either side of hips); this will keep muscle fibers at static lengths throughout the contraction (isometric), and the bench wont move anywhere with you on top of it. After 30 seconds (or exhaustion), immediately stretch whichever tricep opposes the contracted bicep for at least 30 seconds. This will allow for more effective stretching of muscle fibers via inactivation of stretch receptors. Most importantly, this will preserve range of motion - as well as enhance muscular uptake of water, aminos, and nutrients. The bicep example can be applied to any muscle group.
Optimal Contraction for Fiber Growth: when trying to increase muscle size and strength, most apes tend to follow the overall mantra that using a weight that absolutely exhausts muscle groups at about 4-6 reps will generate the conditions for hypertrophy. While it's certainly true that maximal damage to fibers is likely observed from such contractions - this doesn't necessarily translate to optimal recovery and anabolism. Accordingly, a study suggested that classical hypertrophy-oriented routines - coupled with prolonged, maximal isometric contractions, generated the most observable increases in muscle strength.
This translates to a pretty simple modification of typical lifting techniques. Once a chimp has reached the moment of maximal contraction for any given lift, 'clench' the muscle there for a while before beginning the release phase of the lift. To take a standing preacher curl as an example: once the biceps and forearms are basically parallel with the chest (or as close to parallel as they'll go), stabilizer muscles are doing much of the work at this point - at least, more than they were at any other point of the lift. Accordingly, while the biceps and forearms are still contracted - believe it or not - they're not maximally contracted. Force yourself to 'clench' the muscles harder, and they will. This is a maximal isometric contraction, and you'll get alot more out of every sequence if this is done towards the end of every set.
Drink water outside of the gym, too: Most apes in the gym down near a gallon of water in the gym while tearing themselves to pieces. Their muscles readily soak up this water, as they've likely gobbled a bit of creatine prior to waddling into the gym. Even if they didn't, muscles quickly fill with water - to be pissed out later as the muscle shrinks back to initial sizes, nutrientless.
The body is bit more complicated than The Sims® makes it out to be. Just like every chimp paces itself for a race, it's optimal to pace the body's intake of water during any given hypertrophy sequence. Figure out your body's optimal water intake (generally a function of BMI, or better, body fat percentage), and shoot for starting and finishing that amount in the gym. If you're still super thirsty, you know you can drink more - but this is suggested to ensure that whatever nutrients might enter muscle tissues will do so. It always helps to drink water whenever consuming protein as well.