Everyone who lifts eventually hits the same question. The weight that felt brutal a month ago now feels manageable but, should you add more? And if so, how much? Is there a way to know when you’re actually ready, rather than just guessing?
Most of the advice out there is some version of “you’ll know when it feels easy”. This is true in the same way that “spend less than you earn” is true financial advice. It’s correct, but it isn’t much help when you’re standing in front of the rack trying to decide whether to load another 5kg.
This is one of the most common questions in strength training, and the honest answer is that most lifters are working off feel and a couple of rules of thumb. Those rules are fine. But there’s more precise ways to think about it, and these are worth understanding.
The traditional rules
There are a few established methods for deciding when to go heavier. They’ve been around for decades because they’re simple and they get the job done for most people most of the time.
The 2-for-2 rule. This is the classic. If you can complete two more reps than your target on your last set, for two workouts in a row, it’s time to add weight. So if you’re aiming for sets of eight and you hit ten on your final set two sessions running, you go up. It’s a sensible, conservative approach that stops you adding weight on the back of a single good day.
Double progression. Here you work within a rep range rather than a fixed number. Say your target is three sets of eight to twelve. You stay at the same weight until you can hit twelve reps on all three sets, then you increase the load and drop back down to eight. You progress reps first, then weight. Hence “double” progression.
RPE and reps in reserve. A more subjective but flexible method. You rate how hard a set felt on a scale, or you estimate how many reps you had left in the tank. If your working sets are consistently feeling easier (more reps in reserve at the same weight), that’s your signal to add load.
These all work. Especially for a beginner, you almost can’t go wrong with simple linear progression: add a small amount of weight whenever you complete your target reps, and keep going until you stall. The reason these methods persist is that they’re good enough, and they don’t require anything beyond a notebook, or a workout-tracking app, and some honesty with yourself.
The Korvi app already helps you handle this logging side. Using Korvi, you can record your reps and weight for every set. Even better, Korvi lets you tag each set with an RPE, so the trend sits in one place rather than scattered across a notebook or three different apps. We built this app with the science in mind. We want you to be able to track the inputs that tell you exactly when to progress. Not just for beginners, but also for the more advanced trainers.
Where the traditional rules fall short
The problem with all of the above is that they rely on either counting reps or judging effort, and both have blind spots.
Rep counting only tells you something at the edges. If you can suddenly do twelve reps where you used to do eight, sure, you’ve clearly got stronger. But that’s a big jump, and a lot happens before you get there. You can be getting meaningfully stronger week to week without the rep count changing at all, because the weight is moving more easily even though you’re still stopping at eight.
Effort-based judgement has the opposite problem. It’s available on every rep, but it’s subjective and easily fooled. How hard a set feels is affected by your sleep, your stress, your caffeine intake, how the previous exercise went, and your mood that afternoon. Two identical sets can feel completely different on two different days. Research backs this up: how hard a set feels subjectively, may not be the most reliable predictor of true training intensity and readiness.
So you’re left with a slow signal (reps) and a noisy signal (effort). Neither tells you what’s actually happening to your strength in real time.
The more precise answer: bar speed
Here’s the idea that changes how you think about this question. When you lift a given weight with maximum intent, the speed the bar moves at is a direct readout of how hard that weight is for you, right now, on that day.
This is the basis of velocity-based training, a method that has been used in elite strength and conditioning for years. The principle is simple. For any given load, a faster bar means that weight is easier for you. As you get stronger, the same weight moves faster.
The useful version of this for answering “should I go heavier” is something coaches call contextual velocity, which just means comparing your bar speed today against your own bar speed in the past at the same weight. If you’re benching 80kg and over a few weeks your average bar speed on that load climbs from 0.4 metres per second to 0.5, you are unambiguously getting stronger, even if you’re still doing the same number of reps. The weight is moving faster because it’s easier for you. That’s your green light to add load.
As one VBT coach puts it, your bar speed at a given weight increasing across most weeks is the clearest possible sign you’re lifting the same weights more easily, which is the definition of getting stronger.
This sidesteps both problems with the traditional rules. It’s not waiting for a big jump in reps, so it catches progress early. And it’s an objective measurement rather than a feeling, so it isn’t thrown off by whether you slept badly or had a stressful day. The bar either moved faster or it didn’t.
It also helps in the other direction. If your bar speed at a given weight is consistently down compared to your recent average, that’s a sign you’re under-recovered, and pushing to add weight that day is probably a mistake. The same data that tells you when to progress also tells you when to back off.
Bar speed is the best-evidenced piece of all this, which is why we’re describing it here. The research goes back decades and you can check it yourself. But, it’s only one slice of what happens when you lift: a single number, how fast the bar travelled, pulled out of a movement that takes place in three dimensions.
Where does Korvi fit?
Korvi is built to add dimensions to your training, beyond things like bar path velocity. Rather than capturing just that one number, the system is designed to record the full movement of each limb in six axes. Taken together, these map the precise orientation and path of each limb through the whole rep. Bar speed falls straight out of that. So does bar path (see previous blog), range of motion, left-to-right asymmetry, and whether your movement holds together or breaks down as you tire.
A velocity tracker tells you how fast the bar moved. We’re aiming at the bigger question. What did your body actually do? This is the one question that drives genuinely useful, holistic coaching.
How much weight should you actually add?
Once you’ve decided you’re ready, the question of how much to add is more straightforward, and the traditional guidance holds up well enough here.
For upper body lifts (bench, overhead press, rows), the smallest jump you can make is usually the right one. That often means 2.5kg total, or less if you have access to microplates. Upper body lifts involve smaller muscle groups, and a 5kg jump on a bench press is a big relative increase that can stall you quickly.
For lower body lifts (squat, deadlift), you can generally add more, because the muscles involved are larger and stronger. 5kg jumps are reasonable, sometimes more early on.
The mistake most people make is adding too much, too soon, chasing the feeling of progress. Smaller, more frequent increases will take you further over a year than big jumps that burn out after a month. If you have microplates, use them. Adding 1kg every couple of weeks adds up to far more over time than adding 5kg and then stalling for two months.
What this looks like in practice
If you want to apply this without any technology, you can approximate it. Pay attention to how the bar moves on your working sets, not just whether you complete the reps. When a weight that used to grind starts moving crisply, that’s your bar speed telling you something, even if you’re estimating by feel. Lift with maximum intent on every working rep so the speed actually means something, and keep a basic log so you can spot the trend.
The limitation, of course, is that you can’t actually see your bar speed. You can feel roughly whether a rep was fast or slow, but you can’t measure that 0.4 became 0.5, and you certainly can’t track it accurately across weeks of training. The precise version of this has, until recently, required equipment that costs upwards of £2,000 and lives in university labs and professional facilities.
This is a large part of why we’re building Korvi. The goal is to put objective movement data in reach of regular lifters, rather than just elite athletes with sports science budgets. Knowing exactly when you’re ready to go heavier, backed by your own data rather than a guess, is exactly what we’re building toward.
We’re not all the way there yet. The sensor hardware is still in development, and getting accurate velocity data from a body-worn device to your phone reliably, in a normal gym, is a genuinely hard problem we’re still working on. But the principle is sound and we’re continuing to find strong evidence.
For now, the traditional rules will serve you perfectly well. Add weight when the bar starts moving easily, make smaller jumps than you think you need to, and trust the trend over and above any single session. The data just makes the same decision even sharper.
If you want to go deeper on lifting technique, our guide to bench press bar path covers another area where small adjustments make a big difference.
Korvi is building wearable sensors for strength training, with full 3D motion tracking, the potential for bar path analysis, and AI-powered coaching. The app is free and available now on the App Store, with Android coming soon. The sensor system is in development, with a Kickstarter launch planned for 2027.