You want to get the most out of your training, right? Right. So knowing things like the importance of time under tension, what to feed your muscles post-workout, and the ideal rep range to recruit fast-twitch muscle fibers are all crucial pieces to the puzzle.

If you have no idea what any of that means, you’re about to get schooled. And if you do know, you’re due for a refresher.

For How Long Should I Be Sore After a Workout?

Answer: It varies.

A person’s fitness level paired with how intense the workout is will determine the degree of soreness someone will experience. “It will vary from individual to individual, but on average most people will experience soreness for one to three days after a workout,” explains natural professional bodybuilder Mike Lipowski, owner of Pure Physique Gym in Shrub Oak, NY, and author of Pure Physique: How to Maximize Fat-Loss and Muscular Development

However, there’s also something called delayed onset muscle soreness, which is discomfort and soreness that gradually increases 24 to 48 hours after the workout is complete. It’s normal, and simply means that you’ve exercised your muscle beyond its comfort zone.

While experiencing soreness after putting your body under physical stress is expected, Lipowski cautions against using how sore you become to gauge workout effectiveness. “If you stood on one foot for an hour, your leg would probably get really sore. But was that an effective workout? No, it wasn’t.”

What Should I Eat After My Workout?

Answer: Protein

Protein is essential to help repair and grow muscles, so look to consume a fast-digesting whey protein shake 30 to 60 minutes after your last rep. Whole food sources like chicken, lean beef, turkey, and eggs are also quality options.

“Your size will determine,” says Lipowski. “For most men, 20 to 30g is a good sweet spot. Someone who is larger will want to be in the 40g range. Women are typically in the 15 to 25g range.”

Round out your meal with fast-absorbing carbs. “Stuff you’d normally avoid, like sugar, maltodextrin, is fine after a workout because it can help transport protein and amino acids to the muscle a little faster,” he says. “Aim for a 1:2 or 1:3 ratio of protein to carbs, and keep fat content below six percent.”

Can I Out-train a Lousy Diet?

Answer: Not a chance.

“People who try to train harder to make up for a poor diet end up exhausting themselves, and their workouts become unproductive,” Lipowski says. “It’s a double whammy.”

The moment you surpass your body’s caloric threshold, even if it’s by one measly calorie, that calorie gets stored as fat.

“Exercise can make up for some extra calories, but the way most people eat, the number of extra calories goes beyond what they’ll burn during a workout,” he says. “And if you tried to —say, 1,000 or so—doing so would escalate the degree of stress on your body and make it more difficult to recover.”

How Many Reps Should I Do?

Answer: As many reps as it takes to achieve a desired time under tension.

TUT is the total amount of time a muscle is placed under stress during the length of a set. Your cadence, or tempo, for each rep determines your TUT. For example, if you’re using a 3/1/3 cadence (three seconds on the positive portion of a movement, pause for one second at the apex, and then take three seconds on the negative) for seven reps, your time under tension for that set is 49 seconds.

“The number of reps is relative to TUT that someone is shooting for,” he says. “The best range to recruit fast-twitch muscle fibers typically falls between the 20-and 45-second range if the weight is heavy enough; target 45 to 70 seconds for mixed-muscle fibers; and 60 to 90 seconds is ideal for slow-twitch muscle fibers,” Lipowski explains.

Slow-twitch muscle fibers are utilized during endurance activities; they’re smaller and weaker than fast-twitch muscle fibers, which possess the most strength and potential for growth. Mixed muscle fibers use—you guessed it—a mix of both. Regardless of TUT, if you’re reaching muscular failure on a given set you’re recruiting as many fast-twitch muscle fibers as possible.

Is Cardio Training Necessary for Weight Loss?

Answer: No.

“If you derive mental satisfaction from doing cardio and you enjoy the release of endorphins, I’m not going to tell you not to do it,” says Lipowski. “But anaerobic exercise is not necessary for weight loss; to lose weight you need to achieve a caloric deficit.

According to Lipowski, implementing five to 10 minutes of high-intensity interval training)—blending surges of intensity with periods of low intensity—will help stimulate metabolism and spur weight loss. “It doesn’t have to be on a treadmill or recumbent bike, either,” he explains. “Anything you can do in short bursts with all out effort, including burpees, jumping rope, and mountain climbers.”

Should I Train to Muscle Failure Every Set?

Answer: No.

Since the body is an adaptive organism, once it gets used to something—even training to failure—you won’t see as many benefits.

“I used to train to failure every exercise of every workout for years on end, and it definitely led to plateaus,” he admits. “Sometimes it’s better to scale things back so you’re not placing so many demands on your body. Try training to failure for six to eight weeks, and then lowing the intensity and increasing the volume for a week or two. And vice versa if you never train to failure.”

How Often Should I Change Up My Workout Routines and Why?

Answer: It depends upon your fitness level.

“I recommend beginners change routines every two to three months,” Lipowski suggests. “I liken it to throwing a baseball—at first it’s awkward and takes up a lot of energy, but as you get better you become more proficient. Lifting is the same way; Changing up too quickly might deprive the person of muscle-gaining benefits.”

Intermediate and advanced weightlifters should plan to switch their routines every three to six weeks to avoid plateaus. However, you can still make small adjustments during each workout. “Instead of changing the entire routine, change up the order of exercises,” he suggests. “For example, during a chest routine you do dumbbell chest press first and pecs deck second one week, and then pecs deck first and chest press second the following week.”

What Are Five of the Best Exercises for Overall Strength?

Answer: Squat, deadlift, shoulders press, legs press, and bench press, but…

Lipowski prefers to look at this in terms of the type of exercise instead of specific movement. “Any five compound exercises will give you a bigger bang for your buck compared to any five single-joint exercises,” he says. “You’ll be told the best are the squat, deadlift, shoulders press, legs press, and bench press—and they do touch on every major muscle group. But any compound movement will involve more muscle groups and have a greater systemic effect on you compared to a single-joint movement.”

That said, if your overall strength in a specific area is lacking you’d want to rely on single-joint exercises to isolate the muscle group and hit it directly.

How Long Should My Workouts Last?

Answer: 30 minutes of “max effort time”.

Where and when you train can alter how long you’ll be in the gym. Waiting for equipment in the midst of a post-work rush will keep you there longer compared to people who work out when the gym is less crowded. Instead of boxing yourself into a set time, focus on how long you’re performing working sets.

“Your max-effort time should fall between 20 or 30 minutes,” Lipowski says. “But when you factor in warm-up and rest time, that’s going to stretch your total time you’re in the gym.”

How Many Calories Should I Consume?

Answer: It varies.

A few factors that determine caloric intake include age, gender, lifestyle, height, and fitness level. “An easy way to figure this out is to use an online Basal Metabolic Rate tool that uses the Harris Benedict Formula.

BMR is the amount of calories you would burn if you pulled a Rip Van Winkle all day. You can find a free online BMR calculator here.