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How to Warm-Up for Resistance Training

Trying to figure out how to warm-up for resistance training using the internet is like walking through a minefield. RRAMP it up & you can't be wrong...
How to Warm-Up for Resistance Training

Ask most people what the purpose of warming-up is and you'll get a mix of responses:

  • It's about limbering up!
  • All you have to do is get your body warm!
  • Stretch so you don't pull a hammy!

Not exactly...

I'm trolling you...

It's not so much about limbering up as it is preparing to move. Lions do dynamically stretch throughout the day, but not immediately before the hunt.

Getting your body generally warm on a piece of cardio equipment is not the same thing as rehearsing skills in a progressive manner.

Passive static stretching doesn't reduce your chances of injury and can actually decrease your performance.

I know there are people out there thinking, "Darren. Why are you complicating the warm-up man? Just hop on a bike for a few minutes, shake your legs and arms out and get to work!"

And ya you could make it that simple I guess, but it'd be a missed opportunity. You won't get that time back. What I'm about to teach you isn't very complicated once you get the hang of it and you'll get considerably more out it in the long-term.

Better Performance

In my last article, I laid out the practical reasons to warm up before you lift. The most important reason though? To improve performance! Naturally...

A meta-analysis looking at 32 high-quality studies on warming up and physical performance found that 79% of those studies found a significant positive trend for improved performance after the warm-up. There is a large body of evidence on warming up and the majority of it is encouraging. At the very least, it's not detrimental.

A warm-up is really movement preparation. And like I said in that last article, it's a wonderful opportunity to practice movements while you're fresh and ramp up your nervous system tone. This is especially important for workouts that require a lot of speed, technique or heavy weight. It's also an amazing opportunity to introduce movement variability too.

Anecdotally, people who prioritize warming up, also tend to complain less about joint issues, fatigue, and other aches and pains. Plus the movement practice helps them develop movement skills faster overall.

Warm-Up Structures

In a world where most people's biggest excuse for not training is time, I've become very sensitive to the time investment of any given warm-up. Thus like everything else I program it's a matter of priorities for the person in question.

In school I learned an acronym called R.A.M.P. because people love acronyms. However within a couple of years on the job I started to also emphasize (self) massage prior to training it's become more of a R.R.A.M.P. in my eyes:

  • Raise (Generalized cardiovascular warm-up for 2-15 minutes)
  • Release* (Often self-massage or foam rolling for 5-10 minutes)
  • Activate (Create appropriate stiffness or stability)
  • Mobilize (Practice movements through your full range)
  • Potentiate (Raise intensity and/or speed)

*My spin. It's rare outside of athletic training environments to have a masseuse on hand.

This gives you a good template for any kind of warm-up actually, not just a resistance training warm-up.

Raise – General Cardiovascular Warm-Up

You might feel as if you get a lot out of 5 minutes of cardio prior to lifting, and that's a very common recommendation. Sadly the research into weight-room performance is surprisingly limited.

Photo by CHUTTERSNAP / Unsplash

Generalized warm-ups are, however, among the most researched components of a warm-up. With the majority of it suggesting that only longer low intensity time durations are better for performance (~10-15 minutes).

For instance, one study found that a 15 minute low-intensity stationary bike was the only statistically significant booster of 1 repetition maximum (1RM) leg press performance. It also compared 5 minutes of low-intensity, moderate intensity and 15 minutes of moderate intensity work. The longer moderate intensity work, lead to the worst performance.

Another paper on elite sprint Kayakers found that 10 minutes of low intensity warm-up, followed by 5 x 10 second sprints (@200% peak power output) with 50 seconds of recovery (15 min. total) yielded the best 1RM bench press performance.

The later suggesting a potentiating effect of speed work that I'll talk about more in depth below.

On its own, moderate intensity cardio actually seems like one of the worst ways to warm-up for resistance training performance. I suspect because it raises body temperature in a non-specific manner and creates excess fatigue along the way.

Why doesn't a high intensity sprint do something similar? Well provided it's short enough, it likely potentiates the nervous system for higher intensity performance.

What happens if you mix more specific intensity ramping procedures?

Well if you only do 1 set of 8 with 50% of 1RM, and another set of 3 with 70% of 1RM, before 1RM leg press performance you see a worse result. Than had you added 15-20 min. of low-intensity generalized cardiovascular activity before hand.

All-in-all, the research suggests that there is a delicate balance between warming the tissues up but not creating too much fatigue to reduce performance.

Frankly, most of the benefits in a resistance training setting seem to require more time than most people spend on cardiovascular equipment during a typical warm-up. Most research papers also don't use anything like what I'm about to recommend to you below.

Conclusion: If you do feel you get some benefit from cardiovascular exercise prior to lifting, go for it. Time permitting.

If it's all you plan to use, you'll likely need at least 10-15 minutes of low-intensity work to make it worthwhile.

Otherwise, I simply don't review this as a requirement anymore. At least not for more resistance training sessions. If it takes 10-15 minutes to get warm, then I'd rather spend that time on more specific movements.

Release – Self-Massage

Arguably this could go before or after a generalized cardiovascular activity. For the sake of time, I tend to prefer to prioritize this over cardio.

However, if you're time crunched, this is usually the first thing I drop, which means it's still kind of optional. My rationale being, that it's very easy to do self-massage at other times of day.

Massage enhances any stretching work you do, static or dynamic. I tend to recommend dynamic stretching in the warm-up only (with some exceptions), and keep most static stretching away from resistance training warm-ups.

Static stretching is still very useful, it just reduces neuromuscular training performance when done within a ~20 min. window of speed or resistance training.

As a result, I tend to move most of that away from the resistance training work by creating short mobility routines for off-days, later at night or earlier in the morning. Occasionally I might do some static in a cool-down if time is a factor.

Massage dramatically improves static stretching outcomes. Something about the sensory element of applying pressure that improves flexibility/mobility very quickly. It's most likely the it helps inhibit the neurological tension that restricts your flexibility more than the actual length of any tissues.

This can maximize the effectiveness of any dynamic or static stretching. All seemingly without the neurological "numbing" that happens when you statically stretch.

In a recent meta-analysis of 14 pre-rolling studies, the authors concluded that self-massage pre-workout led to performance improvements, regardless of the massage tool used – foam roller vs roller stick.

A few pieces of cheap equipment can be kept in a drawer at home and done before a daily (or semi-daily) mobility routine. It's also easy to do in front of your TV before bed time, which is very relaxing and can set the tone for bed-time.

The most common tools are:

  • Foam Rollers
  • Stick Rollers
  • Lacrosse Balls (for hard to reach areas in the hips and shoulders)
  • Tennis Balls (less intense version of a lacrosse ball)
  • Golf Balls (for the feet)
  • Peanut Rollers (two tennis balls or lacrosse balls taped together with hockey tape, for either side of the T-spine)
  • And a wide assortment of speciality tools with high prices that I think most people can do without...

I get a lot done with the above. A decent foam roller or stick roller will cost you <$50, a pack of lacrosse balls is ~$20 or less, tennis balls even less, golf balls even less. It's $5 to buy good tape for taping them together.

Considering seeing a good RMT is $100+, you'd be surprised what you can get done yourself for less than that in the comfort of your own home. You don't need to get really really intense tools either.

For instance, I find myself using a tennis ball more these days than a lacrosse ball because a lacrosse ball will always feel sore and you don't need to dig so deep to make self-massage effective.

The link above shows paid members a video of the general sequence I recommend for clients but in a nutshell I use self-massage as a good opportunity to gauge how your body feels prior to training.

Some Key Areas:

  • Calves
  • Outside Thigh
  • Inside Thigh
  • Front of the Thigh (Hip Flexors)
  • Glutes
  • T-Spine
  • Back of the shoulder girdle
  • Lats/Pecs
  • Arm Extensors/Flexors

If it feels sore or stringy, I might spend a minute or more on the area, if it feels pretty good, I tend to move on quickly. I don't want to spend more than about 5-10 minutes here, and the side-benefit is that you will raise your body temperature in a low-intensity environment.

That side-effect sheds some light on why I now tend to downplay a general cardiovascular warm-up.

Activate – Increase Stiffness/Stability

Now we're getting into what I consider to be the essential.

According to McGill et al., short term isometric training of the torso increases core stiffness. This stiffness is vitally important for protecting the spine highly compressive, shearing or spinal traction exercises like squats, lunges, deadlifts, hinges or chin ups even.

It likely leads to performance improvements as a result too. You can't shoot a cannon from a canoe. And your torso is where the majority of your stability comes from so it should be prioritized.

In my Better Scientific Seven Minute Workout (SEMW), I proposed a quick but useful sequence that I still generally use as a starting point for all the warm-ups I build.

It only takes 2 minutes and 40 seconds to get through – 4 exercises of ~30 sec. with a ~10 sec. break.

  1. McGill Curl Up (AKA Crunch or Sit Up) with a 5 second hold (6 reps)
  2. Alternating BirdDog with a 5 second hold (3 reps per side)
  3. Right Side Plank 3×10 seconds
  4. Left Side Plank 3×10 seconds

*Links go to coaching client and members-only content.

Keep in mind that this is merely a good starting point with a low time investment. Like regular training, once these become easy there are a variety of harder variations I like to cycle in and out.

The gist of the time-crunched sequence is:

  • Anterior Core Stability Exercise
  • Rotational Core Stability Exercise
  • Lateral Core Stability Exercise

However, as you become more and more skilled you should probably utilize more integrated warm-up movements. I'm a big fan of medicine balls in warm-ups but you typically need a concrete wall or partner to throw with.

If you have time, I would highly recommend adding:

  • Glute Max Activation (glute bridge sequences typically)
  • Glute Med/Min Activation (mini-band, clamshell or leg raise sequences)
  • Serratus Anterior Activation (Protraction/elevation drills)

These additional movements hit a more complete ratio of all the key areas lacking stability in the average trainee.

Glute Med/Min work aiding more specifically when a person is doing any single-leg work, and Serratus Anterior would likely only be done assuming upper body work was being done this day. The Serratus Anterior is kind of like the glute med of the shoulder.

Priming stability in these areas can take as little as 5 minutes, appears to improve performance during training, and by extension improves the training outcome.


Most people assume that resistance training makes people less flexible. Yet, nothing could be further from the truth.

Study, after study, after study, after study show that resistance training leads to flexibility improvements in a lot of key areas. Even in (Judo) martial artists!

Often as much improved flexibility as you see with static stretching. Although the benefits are likely pronounced in older individuals and effects are stronger at higher frequencies of training.

This makes a strong case for  proper resistance training being enough for most of you to develop and maintain more-than-adequate functional ranges of motion. Most flexibility improvements are really the result of neurological changes anyway.

Due to this lesser known side-effect, you do not have to mobilize to absolute maximum end-ranges in a warm-up for mobility or flexibility improvements.

The purpose of this phase of a warm-up isn't to make dramatic improvements in your flexibility. The resistance training itself will help a great deal in this department. And specialized specific stretching or flexibility techniques can fill in the gaps outside of these sessions.

The purpose of this sub-maximal mobility work is to actively practice and prime your existing range of motion so that you better tolerate it under load. Meaning the best warm-up exercises are somewhat exaggerated lifts that you intend to do in your training session.

KB Overhead Squat = Great way to mobilize for heavier squat work...

Some of my favourite examples:

Warm-Up Exercise Training Exercise
Overhead Squat Front or Back Squat
Best Stretch Ever Lunge
Good Morning Hip Hinge/Deadlift
Push-Up Variation Bench Press
Serratus Slide Overhead Press
Rotator Cuff Drill Row
Pullover Chin Up

I will often program one warm-up drill per expected training exercise, or use hybrid combinations to kill multiple birds with one stone, like the Best Stretch Ever.

I choose exercises that reinforce the movement pattern that I'd like to see later. Typically you want to choose a warm-up exercise that addresses a movement deficiency – if there is one.

These are often called 'corrective' exercises, in the sense that they are designed to 'correct' some subpar part of a movement, or less-than-ideal pattern of movement. If a movement is corrective, you should see the desired change near immediately.

For instance, if you have trouble with squat depth, you may want to warm-up with some kind of static deep squat position like a deep squat curl, or a deep squat and reach. And the person in question should feel more comfortable near immediately at greater depths.

It's important to keep in mind you can't always pigeonhole an exercise as either a warm-up drill or a training exercise. There is overlap.


If you plan to lift moderate to light (>8 reps) weight with less technical lifts, or less stability requirements, then this part might not matter as much. There is little need to spend a ton of time warming up further for arm curl sets of 10 with 30-40 lbs (15-20 kg).

Of course, this is dependent on ability too. While stable machine activity requires less technique and situationally less of a warm-up, you should still be smart about these things.

If you can leg press 315 lbs for 15-20 reps, I do not recommend doing some bodyweight squats and then going to town with that weight. Yes, that's a pretty moderate to light weight for you, but it's still fairly heavy in the grand scheme of things. You may still want at least a potentiation set or two – AKA warm-up set.

If your more of a 135 lbs or 185 lbs kind of lifter for that rep range, then you might have less of a need for potentiation sets.

On the other hand, you plan to lift reasonably heavy (fewer than 8 reps), with more technical compound lifts, or lift with high speeds (jumping or the Olympic lifts) then you may want to potentiate the nervous system next.

There is a phenomenon that strength coaches (like me) exploit called Post-Activation Potentiation. I won't get deep into the details but there are potentially multiple ways we can improve performance by manipulating plyometric and/or very heavy resistance training immediately before doing something else.

Remember that weird effect on the kayakers above? Whereby 10s on, 50s off sprints, improved bench performance better than 15 minutes straight of light intensity work?

That's an example of a potentiation effect.

Potentiate means to increase the power, effect, or likelihood of improved performance.

Now the specifics are a closely guarded secret...

I'm kidding, we know there is an effect, but I wouldn't say we know exactly how to maximize the effect.

With this in mind the last few exercises we choose for a warm-up should ramp up the nervous system output. You increase the intensity to a point where subsequent activities can be performed at a maximal level.

I often do this with jumps and throws, and/or calculated increases in weight.

For example, let's say there is a heavy squat in your training routine. You may have done some kind of bodyweight or lightly loaded squat during the mobilize part of the warm-up. Here we might introduce a vertical jump or a progression of a vertical jumps for potentiation. Preceded by or followed by say one  warm-up set @50% your estimated working weight, and another warm-up set at 75% of your estimated working weight.

You don't need to do this for every exercise in your workout, but you may want to do it for a few key ones in certain situations.

Primer on Warm-Up Sets

That brings me to warm up sets, which generally only apply to more technical compound lifts. Anything that you can load it considerably, requires excellent technique and moves a lot of muscle. Usually it’s some of the first 2-4 or fewer exercises in a routine. More often the first one or two.

There are lots of ways to do warm up sets, and every coach has their own method/madness. Near as I can tell, few are grounded in strict science and fall under the umbrella of "the art of training," but they work. At least, when you figure out what works for you.

This requires anticipating your working weight(s). Anticipated working load means the maximum load you anticipate you'll tolerate for however many repetitions you’re attempting to do. I recommend working up fairly heavy in relation to the working weight you expect.

At least one paper found that warm-up sets at 80% of working weight led to a much better performance than warm-up sets done at only 40% of your working weight, at least in the lower body. It might not matter as much as in the upper body.

If you burn out quickly, you may want to use less reps and ramp up the weight faster. If you find that you only really get going on work set 3, then you probably could have used a slower ramp and heavier loads. The heavier the weight you use, the more warm up sets you should probably use.

For instance, I’m fond of the following as a starting point:

  • 50% of anticipated working load (for the same # of reps)
  • 75% of anticipated working load (for the same # of reps as the work sets)
  • 90-95% of anticipated working load (meaning this is your first work-set)

Assuming you’re using 6–15 reps or so. If I'm working heavier, or find that I don't hit my stride until later I will extend this out into maybe something like:

  • 50% of anticipated working load
  • 70% of anticipated working load
  • 80% of anticipated working load
  • 90% of anticipated working load (first work-set)

Or maybe even 50–60–70–80–90% so my first work set happens on #5. Could be 60–70–80–90%, the point is to show you a trend, not a specific way to warm-up. I know a lot of people don't like math either – it's one of my gym superpowers – but you could also just use typical jumps with the equipment you're using.

Like you add 45s, until you get close to a working weight, then 25's, then 10's. For instance:

  • 135 lbs
  • 225 lbs
  • 275 lbs
  • 295 (first work set)

These are simple and effective ways to work up to a decent working weight (unless you're an absolute beast in the gym).  Frankly, I find that in a 6-15 rep range, 2 warm up sets is enough. If you're in a 1-6 rep range, you may want to extend the warm-up a bit. I've taken as little as 3 and as many as 8 warm-up sets in that range.

Some other recommendations?:

  • I personally don't see the need to practice with 'just the bar' but you'll see that as a common recommendation (see the research paper above) – I've never found the barbell to be a good representation of what the movement will feel like with plates on it.
  • I think you should start with with ~50-60% of your anticipated working weight.
  • Don't do too many more reps with lighter weight for your warm-up sets. You want to prep your nervous system here, not fatigue it! No reason to do 15-2o reps in a warm-up if you're lifting >8 reps (I think 6-8 is better). But sets of 5 might be fine if you're going for a max double later.
  • Count anything above 85-90% of your anticipated working weight as a work set. You can keep "working up" within your work sets, it's just smaller jumps typically. Anything within about 4 reps of your max will give you a training effect. i.e. If you're benching 200 lbs for 8, and you do a set of 170-180 or higher, count it as a "work set."
  • This process is not necessary for most isolation exercises

Putting It All Together

Utilizing this framework presents you with options to experiment with. It's up to you to determine what works for you. Customize it to the time you have available and the kind of training you're about to do.

Do some low-intensity cardio before you train if you like – I personally don't, but several of my clients do because it works for them.

Your warm-ups can and will easily last 20 minutes if you include it and do everything else.

Do some foam rolling before you train if you like instead or in addition to – I personally start here, but not if I'm pressed for time and I've been consistently rolling at other times in the week.

Create a little core stiffness. Feel free to steal the 3 move minimum I recommend above. If you have more time, I'd recommend 3 more, all of which will overlap to a degree with mobilizing.

Then practice what you're about to do a little bit before slowly increasing the load or speed on your main exercises for the day.

I do my best personally to keep my warm-ups to under 15 minutes, and more typically 10 minutes if I have to sneak a session in between clients. Here's what it might look like in more specific context:

Conventional “Bodybuilding”

i.e. you’re using moderate to light resistance training loads (6-20+ reps) with more isolation exercises…

  • 2–5 min. of light aerobic activity (*optional)
  • ~5 min. of foam rolling/self-massage (*optional, but highly recommended)
  • 3-6 activation exercises
  • 3-9 practice movements for compound lifts you intend to do for
  • 1-2 potentiation or warm up sets for any 1-4 heavy compound movements you might do early in the training session

I'd say you should be able to keep your warm-up under 15 minutes, possibly closer to 10 for this context. At least, once you know what you're doing.

You probably don't need many practice movements if you're using a lot of machines, or isolation exercises. You may even want to skip to 1-2 warm-up sets if you're pressed for time.

Although some of that work will certainly keep your joints feeling good, it could fall on an off-day in the form of active recovery too.

If you’re deadlifting, practice your hinge. Doing bench press? Do a few push ups at least. It’s generally OK to ignore any isolation movements you might be doing later in a workout. Larger compound movements will prep smaller muscles in this context anyway. So the deadlift will prep your hamstring curls. The bench press will also prep your triceps extensions. No need to do warm-up sets for every single exercise, just the key ones at the start.

Conventional Strength Training

i.e. you’re using less than 6 reps, at 82-85% of 1RM or higher.

  • ~2–15 minutes of light aerobic activity (*optional)
  • ~5 minutes of foam rolling/self-massage (*optional, but highly recommended if you feel it improves your performance)
  • 3-6 activation exercises
  • 3-9 practice movements for compound lifts you intend to do for
  • 3-8 potentiation or warm up sets for any of the 1-4 (probably only the first 2) heavy compound movements you might do early in the training session

Your warm-up could easily last up to 20-25 minutes in this context.

This is a heavier rep range, making it more intense. This likely warrants a longer warm-up. The heavier (closer to 1-2) the weight, the longer it will take. The lighter it is (closer to 5-6) the less it can take (2-3 warm-up sets might be sufficient).

Again, you should feel it out, and figure out how to approach your warm-ups based on your desired outcomes. The same way a basketball player works on their free-throw shooting routine.

Obviously time is also a factor here. That's also a constant balancing act. I'm not trying to break any records so I personally tend to ramp up my 3-5 rep ranges in 3-5 warm up sets. Keep in mind my nervous system is on the twitchy side (former sprint athlete) and I rarely do more than 5-6 sets of anything (even <3 reps) these days.

If you're competing in powerlifting or Olympic lifting, you will need to do a lot of sets to become elite and that includes warm-up sets.

Power/Mixed Sport Strength Training

i.e. you’re using a mix of methods, usually including plyometrics/shock training/explosive training combined with heavy loads and moderate load training is ideal.

  • 2–15 minutes of light aerobic activity (*optional, and better if it's sport specific)
  • ~5 minutes of foam rolling/self-massage (*very optional, real massage preferred)
  • 3-6 activation exercises
  • 3-6 more training specific practice movements, including light ballistic movements
  • 1-5 plyometric or explosive exercises (jumps/sprints/wickets/etc…) ramping up with long rest intervals. This takes a while, but prevents too much fatigue from building up. i.e. Run at 60%, rest, 70%, rest, 80%, rest, 90%, rest, 100% output. The last 2 are 'work sets.'
  • 2-5 potentiation or warm up sets for any of the 1-4 (probably only the first 2) heavy compound movements you might do early in the training session

Your warm-up could last 30 minutes or longer some of the time. I think you want to get into the ballistic/plyometric stuff faster. Something like the FIFA 11 could be in play here if it were soccer, let's say.

A lot of mixed sports will do resistance training after the technical work because speed is harder to train/develop.

Tangent: Endurance activities are another beast entirely, with resistance training also being done afterwards. You could consider the sport itself one long cardiovascular warm-up, but I would still take the opportunity to warm-up as you might for conventional or strength sport training afterwards.

The mistake that a lot of endurance sport athletes make in my mind, is using high rep training. They are already doing that kind of work, so low rep, more pure strength work is ideal for them.

Wrapping Up

You now have a fairly simple framework (RRAMP) that you will have to explore and play with.

Cardiovascular warm-ups take a long time to get through to meaningfully and specifically raise body temp.

They have more value in sport performance, especially endurance sport performance. I tend to steer clear for pure resistance training focus because warming up well already takes a decent amount of time from the workout itself.

Foam rolling is a nice to have, and I probably do it with 80-90% of my clients. But can also take considerably time to complete, if you doddle. And I've seen a lot of people do this in gyms, spend 20 minutes dinking around on a foam roller. Don't do that. Hit the key areas, and move along. Most muscles shouldn't get more than a few rolls.

If you're pressed for time, do a little later. I rarely do it before technical training (like sprints or agility work), mostly because we're out on a field. However, that might change as research dictates.

You might insert some carefully selected static stretching at this point, provided it doesn't interfere with your main lifts on the day. i.e. stretching the hip flexors now, for the deadlift you're going to do first.

Be very selective with this though.

Then follow that up with 3-6 activation exercises for a few key, possibly problematic areas. It might not always be as clear as I wrote above, there are other areas that may warrant some stability work pre-training, like the feet and neck.

I treat design most exercise programs on a 'as needed basis.'

Then follow this up with some specialized warm-up drills, maybe another 3-9 exercises. Typically for a total of 6-12 exercises between activation and mobility drills.

Keep in mind that the mobility work isn't really for improving your mobility. You don't want to decrease stiffness before you lift, you need that for lifting well. Think of this part as maintaining the active mobility you currently have. You may need to do more focused mobility work post-workout, like passive static stretching.

This might be your stopping point some of the time if the weights you're using are low enough. If you're working in a 8-15 rep range, you can ramp up your weights quickly.

If you're lifting pretty heavy though, you will probably want at least 2 (to 5) warm-up sets for the first 1-4 compound technique oriented exercises.

For example:

  • Olympic Lifts
  • The Big Three
  • Bent-Over Rows
  • Chins (maybe lat pulldowns)
  • Overhead Pressing

Keeping in mind that non-direct but similar movement training will warm you up for similar lifts. i.e. Olympic lifting could be sufficient as a warm-up for the bench pressing, bent-over rowing, deadlifting or overhead pressing you plan to do later in the workout.

With practice you should be able to get through a very effective warm-up in under 15 minutes. When I'm pressed for time I can get it down in the 5-10 minute range by eliminating the foam rolling and using more hybrid warm-up drills.

Remember the warm-up only needs to be enough for you to feel like your workout was productive and you performed to the best of your ability. If you feel you can do that without doing any of the above, go for it.

I've simply spent a lot of time researching and implementing these things. These are the commonalities I see between routines. They are not rules set in stone.