Research shows rest periods significantly impact training outcomes. Schoenfeld et al. (2016) found that 3+ minutes rest produces greater strength gains, while 60-90 seconds optimizes metabolic stress for hypertrophy. Shorter rest increases growth hormone but reduces total volume capacity.

The relationship between max weight and reps follows a predictable curve. At 100% you can do 1 rep, at 85% approximately 5 reps, at 75% about 10 reps. This table uses the Brzycki formula: 1RM = weight × (36 / (37 - reps)), which is accurate within ±5% for 1-10 rep ranges.

Posing can make or break your placing. A well-conditioned physique presented poorly will lose to a lesser physique presented masterfully. Arnold famously said he spent 2+ hours daily practicing poses in his final weeks. Posing is also an isometric workout—practice builds mind-muscle connection and burns calories.

Research by Helms et al. (2014) recommends 12-20 weeks of prep depending on starting body fat. Losing 0.5-1% bodyweight per week maximizes fat loss while preserving muscle. Faster cuts increase muscle loss exponentially—a 16-week prep loses less muscle than an 8-week crash diet even with the same total weight loss.

Water loading works by downregulating aldosterone (the hormone that retains water). When you drink 2+ gallons daily, your body increases urination. When you suddenly cut water, the body continues excreting at a high rate for 12-24 hours, creating a temporarily "dry" look. The effect is short-lived—timing is critical.

Progressive overload is the fundamental driver of muscle growth. Research shows that tracking progress increases adherence by 30% and helps identify plateaus early. A PR doesn't have to be a 1RM—track rep PRs too. Adding 1 rep at the same weight IS progressive overload.

Forgetting your belt on squat day or your straps on deadlift day can derail a workout. Studies on habit formation show that environmental cues (like a packed gym bag) are the strongest predictors of consistent behavior. A ready gym bag removes friction and excuses.

Most supplements are overhyped. The ISSN rates only a handful with "Strong Evidence": creatine monohydrate, caffeine, protein, beta-alanine, and citrulline. Everything else has limited or no evidence. Don't waste money—focus on the basics that actually have research backing.

Research shows that total daily macros matter more than food choices for body composition (Aragon & Schoenfeld, 2018). "If It Fits Your Macros" (IIFYM) works because the body processes macronutrients the same regardless of source. 30g protein from chicken = 30g protein from beef = 30g protein from whey for muscle protein synthesis purposes.

Bodybuilding doesn't have to be expensive. Cost per gram of protein is the key metric. Eggs (~$0.04/g protein), chicken thighs (~$0.05/g), and cottage cheese (~$0.06/g) beat expensive supplements. Buying in bulk, using frozen vegetables, and cooking in batches can cut food costs by 40-50%.

The scale lies. Body recomposition (gaining muscle while losing fat) can show zero weight change while dramatically improving your physique. Photos capture what the scale can't. Studies show people who track visually have better body image and more realistic expectations than those who only weigh themselves.

Research uses metric. Gyms in the US use pounds. Food labels vary by country. Converting on the fly causes math errors that compound over time. A 2.5kg plate is 5.5 lbs, not 5. These small errors add up—especially when tracking progressive overload or precise nutrition.