# Partial Reps: Which Ones Are Actually Worth Doing? > Not all half reps are equal. The bottom half, the top half and heavy partials serve very different purposes. - Source: [Musku](https://musku.app/), free strength training tracker for iPhone and Android - Canonical URL: https://musku.app/blog/partial-reps-explained - Published: 2026-09-28 - Updated: 2026-09-28 - Level: Intermediate, Advanced - Language: English - French version: https://musku.app/fr/blog/repetitions-partielles-musculation - Author: Musku (Julien Legrand) _Informational content: this is not a substitute for medical advice. Check with a doctor before starting a training program, especially if you have a health issue or any pain._ Partial reps have a reputation for cheating, and they have often earned it: a half squat with four plates a side is still a half squat. But lumping every partial together misses something useful, because three very different practices hide behind the word. The starting point does not change: **full range remains the default**, for the reasons set out in our article on [full range of motion](https://musku.app/blog/full-range-of-motion). What follows describes the cases where departing from it is a deliberate choice rather than a consequence of the load. ## Three partials with nothing in common | Type | Where the work sits | Example | | --- | --- | --- | | Lengthened partial | Bottom half, muscle stretched | Incline curl through the bottom portion | | Shortened partial | Top half, muscle contracted | Lateral raise through the final portion | | Heavy partial | Short range, supramaximal load | Rack pull, board press | These three do not pursue the same goal and are not worth the same. Confusing them explains much of the circular arguing about the topic. ## The bottom half: the interesting one This is the case that has shifted opinion in recent years. Several studies have compared full range training against training restricted to the **portion where the muscle is lengthened**, and report comparable muscle gains, occasionally slightly favouring the lengthened partials. The proposed explanation matches the one behind stretch tension: that portion carries the highest mechanical stress, so the strongest growth signal. Working only there concentrates the effort on the most productive part of the movement. Two honest caveats. The literature is recent, with varied protocols and modest sample sizes, so restraint is warranted. And full range covers that portion anyway, which makes it the simplest default. In practice these partials work well at the end of a set: once you can no longer complete a full rep, you continue through the bottom half for a few more. ## The top half: the least defensible Shortened partials, the ones where you stop before lowering, are the most common and the least supported by evidence. The load is lighter since the muscle produces less force in that position, and mechanical tension there is low. They produce a strong pump, which explains their popularity, but sensation is not the indicator. Their only defensible use is extending an isolation set at the end of a session, and even then the bottom half would probably do the job better. ## Heavy partials: a strength tool These chase neither hypertrophy nor a pump. They exist to load a specific portion with more weight than you can handle through a full range. - **The rack pull**, a deadlift starting from the knees, lets you load the top portion heavily. See our article on the [deadlift](https://musku.app/blog/deadlift-technique-mistakes). - **The board press** shortens the range to train lockout. - **The partial squat** helps you get used to a load you cannot yet control through the whole movement. Their value is real but specific: breaking through a sticking point, accustoming the nervous system to a load, or maintaining intensity when a full range is not available. For someone chasing muscle, they are not a priority. ## Partials out of necessity One last case, quite unlike the others: shortening the range because part of the movement hurts. That is a legitimate and frequently recommended adaptation, provided you work in the pain-free zone rather than forcing through it. It is not a training strategy but a temporary measure, and it does not remove the need to have persistent pain assessed. Our article on [alternatives for sensitive joints](https://musku.app/blog/exercise-alternatives-sensitive-joints) covers what to substitute. ## Bad partials They all share one feature: **the range shrinks as the load goes up**, without anyone deciding it. The half squat that becomes a quarter squat, the press that stops fifteen centimetres above the chest, the pulldown that only travels halfway: in those cases the partial is not a tool, it is a symptom. The muscle works in its strongest and least productive portion, and the progression shown in your log is an illusion. The test is simple: **did you choose that range before the set, or did it happen to you during it?** ## How to use them without losing the plot 1. **Full range by default** on all your main exercises. 2. **Lengthened partials** as an extension of an isolation set, once full reps stop happening. 3. **Heavy partials** only if you have an identified strength goal, once or twice a week at most. 4. **Always log them**, otherwise your history becomes unusable. That last point is the most neglected and the most costly: a set of 10 full reps and a set of 10 partials look identical in a logbook while having nothing in common. ## Frequently asked questions ### Do partials build more muscle than full range? Those performed in the lengthened position produce comparable results, occasionally slightly better depending on the study, but the gap is small and the literature is young. Full range already covers that portion, which makes it the simplest and most robust choice. ### Should I finish my sets with partials? Not compulsory, and it adds considerable fatigue for an uncertain gain. If you do it, keep it for the last set of an isolation exercise, and work the bottom half rather than the top. ### Is the rack pull useful for building a back? It lets you load the top portion very heavily, which works the traps and posterior chain hard, but it removes the bottom of the movement. It is a complement, not a replacement for the full deadlift. ### How do I know if my range is shrinking without noticing? Film yourself from the side once a month on your main lift, or ask someone to tell you where you actually stop. Perception of range is notoriously unreliable, especially as the load increases. The practical problem with partials is that they make a logbook unreadable unless you flag them. One line in the exercise note in Musku is enough: "bottom partials" or "full range". The following month, comparing two sessions, you know whether your load genuinely went up or whether you simply shortened the journey. That is exactly the difference between progress and the impression of progress.