How LiftShift works

If you choose “Login with Hevy”, LiftShift logs in via your own backend to retrieve a short-lived auth token, then pulls your workouts and converts them into a standard set format used across the app.

If you have Hevy Pro, you can use your API key. LiftShift validates the key and fetches workouts through the official API endpoint, then maps them into the same internal set format as CSV imports.

Lyfta sync uses your API key to fetch workouts and workout summaries, then normalizes them to LiftShift’s set format for analysis.

CSV import is the most universal option. LiftShift detects column meanings (like exercise name, weight, reps, date, and set type), supports different date formats, and converts units when needed.

LiftShift groups your sets by rep ranges to show what your training has emphasized lately: lower-rep sets look more strength-focused, mid-range sets look more muscle-focused, and high-rep sets look more endurance-focused.

The heatmap shows how often you trained over the last year. Darker days usually mean more working sets (and often more total volume). It is best used for consistency, not perfection.

A “set” is one logged set. A “workout” is a full session (a group of sets done in the same workout). LiftShift uses workouts to talk about consistency, and sets to talk about training volume.

Volume is a simple “how much work did you do?” signal. LiftShift counts working sets and uses weight × reps (and skips warm-up sets in most summaries).

Use volume trends to compare training blocks and see whether your workload is gradually increasing over time.

Workout duration is how long your session lasted (when the source data has start/end times). Density is how much volume you did per minute. Higher density often means shorter rests or faster pacing.

A PR in LiftShift means a new all-time best weight for an exercise (based on your logged sets). PRs are tracked per exercise over time and used to show progress “bursts” and droughts.

A PR drought means you have not hit a new best weight recently. This can be normal during phases focused on form, higher reps, rebuilding after a break, or simply repeating weights to get stronger at them.

Sometimes you hit a big PR, but the next sessions drop hard. LiftShift flags this as a “premature PR”: the jump happened, but it did not hold up over time.

This is not a “you failed” label. It is a reminder to build strength in a stable way: repeat the weight, improve reps and form, and make smaller jumps.

LiftShift uses your weight and reps to estimate your “strength level” for an exercise, so it can compare sessions even if you change rep ranges. It is an estimate, not a max-out test.

In the exercise view, LiftShift gives each exercise a simple status based on recent sessions. These labels are meant to be coaching hints, not judgments.

• Getting stronger: a clear positive change (more than about +2%).
• Plateauing: roughly stable (between about -3% and +2%).
• Taking a dip: a clear drop (more than about -3%).
• New: not enough history yet to read a trend.
• Premature PR: a big spike was followed by a drop (unsustainable jump).

Many cards compare a recent window to the window before it (for example: last 7 days vs the 7 days before). This helps you quickly answer: “Am I doing more work lately?”

Consistency is tracked week-by-week. LiftShift counts unique workouts and shows streaks based on consecutive weeks with training.

If an exercise looks “stuck” (same load and similar reps across recent sessions), LiftShift flags it as a plateau and suggests a small next-step: a tiny weight increase for weighted lifts, or +1–2 reps for bodyweight-like lifts.

LiftShift also looks inside a single workout to explain what happened from set to set: did you fade from fatigue, did you pace well, or did you jump the weight too fast?

• Normal fatigue: a small rep drop at the same weight is expected.
• Good progress: you increased weight and still hit solid reps.
• Premature jump: you increased weight too much and reps fell far below what your recent sets suggest.
• Effective backoff: you lowered weight and got the reps you needed for more quality volume.

Training data is noisy. LiftShift can smooth trend lines so you see the bigger picture without overreacting to one great (or bad) day.

You can turn this on or off in preferences if you prefer raw session-to-session lines.

For muscle analysis, LiftShift turns each exercise into “muscle work” based on which muscles the movement trains. It uses rolling 7-day windows so “weekly volume” matches how bodies adapt — not just calendar weeks.

This helps answer questions like: “Am I training back as much as chest?” and “Which muscles are being neglected?”