Terms and Forces

If strength is the ability to produce force against an external resistance, then it helps to know what these forces are and how they resist. We first have to define some terms:

Mass – In practical terms, mass is the amount of matter in a given object. A standard metal 20kg plate may be thinner and smaller (takes up less space) than a 20kg rubber bumper plate, but both have the same mass and will respond to the same force applied to their center of mass the same way. Mass is typically measured in grams (g) or kilograms (kg)

Center of Mass

The center of mass (COM) of an object is the average position of the matter in that object. For objects that are the same material and density all the way through, in symmetrical shapes, the COM will be the visible center. An empty or even-weighted barbell (assuming it’s decently manufactured) is like this, and its COM will be at the center of its diameter halfway along its length.

Most objects aren’t perfectly symmetrical and consistent. For irregular objects, if you could measure the amount of matter and where it was laid out in each direction (X, Y, and Z), you could find the middle position for all three axes, and that would be the COM. Note that, for irregular objects, the COM doesn’t have to be physically touching the object. The COM of a donut is in the center of its hole.

Humans are irregular, too. Our COM (commonly referred to as the center of gravity or center of balance) is different from person to person and second to second (each cycle of the heart involves a change in blood volume that, with sensitive enough equipment, creates a detectable change in our body’s COM). 

If an object does not deform (squish, bend, break, etc.) when a force acts on it, we can think of it as acting on all the mass of the object at the COM.

When you lift a balanced barbell, for instance, you can effectively focus on lifting a single point—the center of the barbell—and know you can move the entire mass of the barbell if you move that point.

Once you lift the barbell onto your back (in the squat, for instance), your COM and the barbell’s COM form a combined COM—so long as the two move together—and it follows the same principles as before. The system’s COM will be somewhere between your COM and the barbell’s COM. The more massive the barbell, the closer the system COM will be to the barbell. If the barbell had the exact same mass as the lifter, the system COM in a squat would be exactly halfway between the lifter’s COM and the barbell’s COM.

Force:

A force is something that, unopposed, would cause an object to change in its motion. For our purposes here, forces either push or pull at a specific point, and how forces affect motion are determined by Newton’s Laws.

Forces are traditionally given in units of newtons (N, metric) or pounds-force (lbf, imperial).

Weight:

Weight is the interaction of the mass of an object with gravity. Technically, then, a 20kg plate doesn’t weigh 20kg—it weighs 196.1N (the attractive acceleration of gravity times the mass), or 44lbf.

This is mostly a technicality for our purposes because gravity is approximately the same around the globe. A 200kg mass weighs 1953N at the point of lowest gravity on the Earth and 1967N at the highest (just a 3 lb. difference)

Position:

Where something is in space.

Velocity:

The change in an object’s position in a unit of time, given in units of distance/time. Classic examples would be meters per second (m/s) or miles per hour (mph).  Technically, velocity also has a direction—using whichever units are appropriate as a reference point (“North,” “Up,” etc.)

Acceleration:

Acceleration is the change in an object’s velocity in a given unit of time, usually given in meters per second, squared (meters per second per second). 

To get a better picture of this, imagine at the start (time zero) that an object is moving downwards at 1 m/s (velocity), and it has a constant acceleration upwards of 1 m/s². After 1 second, the object will have a velocity of zero—it will be stopped. The acceleration changed the velocity by 1 m/s after 1 second (thus, 1 m/s²). After 2 seconds, the object will be moving upwards at 1 m/s.

Momentum is the quantity of motion of a moving body. If you measure every atom in a system and know its motion and sum these together, you know the object’s momentum. Since we model rigid objects as having all their mass at the same point (the COM), we know an object’s momentum by multiplying its mass times its velocity. 

A 4000kg elephant and a 0.1kg mouse could have the same momentum. If the elephant were running, the mouse would have to be launched out of a cannon at ludicrous speed… or both of them could be still (velocity=0). 

Momentum is typically measured in kilogram-meters per second (kg*m/s).

Work:

Work is referred to as ‘force times distance,” W=FD. In mechanical terms, work only applies in the direction of resistance, so if the resistance being measured is gravity, work only accounts for the force we apply upwards.

Although useful to clarify, we rarely apply for work directly in strength training. A 100 lb. snatch moved quickly from the floor to overhead and a 100 lb. dumbbell carried from the floor to the shoulder and then pressed overhead with one arm are two very different training stimuli, but they each imply the same total work.

Power:

Power is work/time. If a 500lb weight is deadlifted in one second or eight seconds, the one-second deadlift was a far more powerful movement.

General Principles for Novice Strength Program Design:

• • Learn the lifter’s scheduling needs and select session frequency/timing first to make training feasible for their life schedule.
  • Choose exercises that efficiently cover a broad range of strength demands.
  • Choose exercises that require some skill to do correctly but aren’t so difficult to learn that they prevent progress.
  • Choose exercises based on the trainee’s available equipment. 
  • Choose a stimulus that is specific to developing strength but balances between extremes which bring unmanageable tradeoffs. For example, heavy singles and sets of twenty contribute to strength, but their places on the rep scale’s extremes mean they become unwieldy in practice and train a narrow window of ability. 
  • Use simple progression and demonstrate progress with technique, increased weight on the bar, and whatever metric the lifter cares about.
  • Stay at high enough intensity and high enough volume to see progress. 
  • Keep it simple, hard, and effective.

  In the details, each of the variables breaks down as follows:

Session Frequency

Most lifters aren’t gym rats—they balance the costs of training (in terms of time, money, and stress) against the benefits. The coach should set session frequency to offset the costs of getting to the gym multiple times a week, the session length, and the lifter’s need to recover.

The lifter needs enough exposure to maintain technique and collect enough volume to grow while allowing for recovery and fitting their life schedule needs.

Our recommendations are varied, ranging from 2-5 days, because the lifter’s needs can be quite varied. Two-day schedules are usually reserved for older lifters, those with constrained schedules, and athletes with sports practice that competes for time with their strength training. Five-day schedules are rarer for the novice but sometimes useful as a first step to those transitioning to high volume/frequency intermediate programs or for those who need/want more frequent exposure to the lifts for technique practice. We recommend most novices train 3-4 days a week.

Session length will vary, but sessions rarely need to last longer than an hour for the rank novice. If they’re running long, this may mean the lifter is taking their time warming up, is resting too long between sets, is using too heavy a starting weight, or has been prescribed unnecessarily high volume.  As weight increases and rests become longer, full-body training sessions often stretch out to 75 or even 90 minutes. Be aware of this. Communicate with your lifter to make sure that’s acceptable, and make adjustments as needed. 

Note that a session refers to heavy training stress. If a lifter needs greater frequency—for personal enjoyment, for more frequent practice of certain lifts, or because they are combining strength training with recreational activity or sport—light or practice sessions can add a few sessions to a week without too much impact, if managed well.

Exercise Selection and Complexity

One way to think about these alternatives is to “scale” lifts by their complexity. More complex movements are more technical, less predictable, and require a lower load, and vice versa for lower complexity movements.

The barbell lifts fit somewhere in between, and in our experience, they strike a happy medium. They are complex enough to require skill but simple enough for novices to learn them quickly and easily. Consider them on a scale, balanced against the extremes:

On the low complexity side, we can present an incredible stimulus with electromyostimulation (EMS), for example, but it would be hyper-specialized and, without any skill component, likely won’t transfer well. On the high-complexity side, we begin to increase risk. In complex but controllable environments (say, parkour or acrobatics), the lifter has to keep the stimulus low until their skill is high enough to handle the uncertainty.

This is (among other reasons) why we don’t do BOSU ball deadlifts or wobble-board squats. They introduce unpredictability and complexity that require us to dramatically reduce load without being specific or useful to any particular skill.

As we get closer to the center, we see a number of options that may be more effective for different reasons:

As we get closer to the center, though, we see a number of options that may be more effective for different reasons:

On the low-complexity side, if the lifter is recovering immediately post-injury, is very weak, or needs to focus on a specific piece of a movement, these lifts help keep movements predictable. 

On the complex end, barbells and other equipment were created to reduce complexity and make lifting heavy loads logistically feasible. When they aren’t available, more complex lifts are usually the next option: things like dumbbell, bodyweight, and odd-object movements. In addition, as with Strongman, GORUCK, CrossFit, and other communities, the increased risk and variability may be part of the identity and community that the lifter values. As long as you understand the tradeoffs, you can make the right choice.

Rep Selection 

Rep selection becomes a tradeoff between intensity—getting heavy enough work—and volume—getting enough total work—while maintaining technique and “shooting the middle” for strength.

Ranges are provided here. Sets of 1-2 reps tend to be too heavy for novices to maintain form, require too many sets to collect enough volume, and are so short that they’re primarily phosphagen and don’t tap the fast-glycolytic energy system, which is important for most real-life tasks requiring strength. 

Sets of 11-15 still involve strength-centric energy systems and are still somewhat predictable in relation to 1RM, but in novices, form tends to break down and the weight is suboptimally light. Sets of 3-10 are something of a sweet spot across novice programs. Fives are convenient in our base-10 numeral system, and they effectively shoot the middle of the effective range, but it’s important to remember that there’s nothing magical about 5s that make them more effective than 4s or 6s.

Luckily, the novice doesn’t need to be optimal at this point. If you keep the starting weight reasonably light,  you could make a “mistake,” using a volume that would become too high as intensity progresses, and adjust the volume down as needed through the program. 

Through repeated experience with our BLOC coaches and by reviewing the novice programs of other expert coaches and those who specialize in frailer populations like Dr. Jonathan Sullivan, we have come to these general ranges for sets:

Core Lifts:

• Lower body heavy sets of five:
  • 2-7 sets/session
  • 6-16 sets/week
• Upper body heavy sets of five:
  • 3-9 sets/session
  • 5-20 sets/week

Accessory lifts 

• Flexible
  • If using barbell or dumbbell accessories, 3-4 sets of 8-12 reps is a good starting point for most exercises in a session.
  • Other options are discussed in the novice conditioning lesson.

It’s better to bias the volume a little high for a healthy young athlete, especially when starting with a conservative load. You can always drop sets later. For older lifters or those with known recovery issues, we recommend starting in the lower-to-middle end of this spectrum, building up work capacity while increasing the load, and then increasing volume as appropriate.