The Pre-Production Sample Approval Checklist for Activewear Buyers - Custom Yoga Leggings Manufacturer

A pre-production (PP) sample is the last physical checkpoint before your activewear order becomes thousands of cut, sewn and packed units. Once you sign it off, that garment becomes the legal and technical reference for the entire production run. Approve it too quickly and you inherit every mistake at scale; review it methodically and you eliminate most bulk defects before a single roll of fabric is cut. This checklist is written for brand owners, sourcing managers and distributors who need a repeatable way to approve a PP sample in activewear — where four-way stretch, moisture management and high-recovery fabrics make errors far more expensive than in woven apparel.

What a PP Sample Actually Is (and What It Is Not)

Buyers often use “sample” as a single word for several very different documents. Confusing them is one of the most common causes of disputes later. Clarify which one you are holding before you start reviewing.

Proto / development sample: An early construction study. Fit and materials are still fluid. Not approvable for production.
Fit sample: Used to lock pattern and grading. Usually made in a stock or substitute fabric.
Salesman sample (SMS): A presentation-quality piece for trade shows and buyer meetings. Not necessarily built on production lines.
PP sample: Made on the actual production line, using the actual approved fabric, trims, threads and machinery, with the actual pattern and the actual operator skill level. This is the piece you approve.
Top-of-production (TOP) sample: Pulled from the first bulk output, a few days into manufacturing. It confirms that what was approved is what is actually being made.

If a supplier offers you a “PP sample” sewn in a sample room by a senior technician, you are not looking at a PP sample. Ask explicitly whether it was produced on the bulk line. In activewear, where the difference between a sample-room bonded hem and a factory-line bonded hem can be a 20 % failure rate, this question alone protects your margin.

Before the Sample Arrives: Set the Reference Pack

You cannot judge a PP sample against memory. Assemble a signed reference pack and send it to the factory before production starts. A complete pack typically contains:

The approved tech pack with the latest revision number and date, including measurement charts per size.
Color standards — physical swatches or lab-dip cards, not screen images.
Approved fabric and trim cards, with lot or batch references.
The last approved fit sample, clearly labelled “fit approved, construction not approved.”
Label, hangtag, polybag and carton artwork with dielines.
Any compliance test reports already issued (fiber content, colorfastness, restricted substances).

Number every revision. When a dispute arises, the sentence you want to be able to write is “per tech pack revision 4, dated 12 March,” not “we discussed this in a call.”

Step 1 — Measurement Audit

Measure the garment flat, relaxed, and again after a 24-hour rest, using the method stated in your tech pack. Most activewear factories measure the relaxed garment; some measure after light steaming. Pick one method, write it down, and apply it consistently for every size and every future order.

Check every point of measure in the chart, not just the three or four easiest ones.
Record actual values and the deviation from spec, in centimetres or inches — never “looks fine.”
Apply a written tolerance band. Common industry tolerances for knit activewear are ±1 cm on body points under 50 cm and ±1.5 cm on larger spans, but state your own numbers.
Flag any measurement at or beyond the edge of tolerance as a fail, even if the garment “fits.” Bulk production will vary around the sample; a sample already at the limit guarantees out-of-tolerance bulk.

Also check grading consistency. If you receive multiple sizes, compare the delta between them against your grade rules. A sudden jump between M and L usually signals a pattern or marker issue that will repeat across the whole run.

Step 2 — Fabric, Hand Feel and Stretch Recovery

Activewear lives or dies on how the fabric behaves when worn and washed. This is the step buyers skip most often, because it feels subjective. Make it objective.

Weight and composition: Confirm grams per square metre or ounce weight, and fibre blend, against the approved card. A 5 % shift in elastane content changes recovery dramatically.
Stretch and recovery: Measure a marked 10 cm section relaxed, stretch to a defined load, then release and re-measure after 60 seconds. Record the percentage growth. Compare with the approved standard.
Hand feel: Assess softness, drape, surface smoothness and — critically — whether the fabric “recovers” rather than bagging at the knee, hip or elbow.
Shade and lot: Check the sample against the physical color standard in daylight, then in a light box. Note the fabric lot number on the approval form, and require the factory to reserve that lot for your order.
Transparency: For light colors and lighter weights, hold the fabric against a bright light and, ideally, do a squat or stretch test. Stretch opacity is a frequent complaint in leggings and is invisible on a flat lay.

Step 3 — Construction, Seams and Stitching

Construction defects in activewear rarely appear as loose threads; they appear as seams that fail under tension. Inspect with the garment turned inside out.

Seam type match: Confirm flatlock, overlock, coverstitch and bonded seams are exactly as specified, at the correct seam allowance and needle spacing.
Stitch density: Count stitches per inch or centimetre on a representative seam. Too few encourages seam slippage; too many cuts the fabric.
Seam strength: Perform a manual pull test at the crotch, side seam, waistband join and armhole — the four highest-stress points. Note any grinning, cracking or thread break.
Elastic and waistband: Check elastic width, stretch, and whether the waistband rolls, twists or stays flat after being stretched and released.
Bonding and taping: If bonded, check bond width, uniformity and that the tape has not delaminated from the fabric at the edges.
Ends and finishing: Bartacks, bar tacks at stress points, clean thread trimming, and no skipped stitches anywhere on the visible surface.

Photograph every defect with a ruler or coin in frame for scale. A defect list with images and quantity estimates is far more actionable for a factory than a written complaint.

Step 4 — Fit and Wear Test

A PP sample must be worn, not just inspected. Put it on a fit model matching your target size set and perform a short movement protocol: deep squat, forward fold, overhead reach, jog in place, and a shoulder rotation.

Watch for ride-up at the waistband, creep at the leg hem, and gapping at the neckline or armhole.
Check that the garment does not become translucent under stretch.
Confirm that the fit matches the approved fit sample — a PP sample can be perfectly made and still be the wrong fit if the pattern was altered after fit approval.
Note the model’s height, usual size and body measurements so the feedback is reproducible.

Step 5 — Wash and Care Testing

Before approving, wash the PP sample exactly as the care label instructs and as a customer would, then re-measure and re-inspect. Recommended protocol:

One home-laundry cycle at the label temperature, normal detergent, no fabric softener.
Line or tumble dry per the label, then rest 24 hours before measuring.
Compare all measurement points to the original sample and record shrinkage percentages.
Check for color bleeding onto a white cotton control swatch, surface pilling, snagging, print cracking or peeling, and loss of stretch recovery.
Repeat for three cycles on at least one piece if your category is high-wash (training, yoga, swim-adjacent).

Shrinkage is not a defect if it is known, controlled and disclosed. It becomes a defect when it is a surprise to you and to your customer.

Step 6 — Labels, Packaging and Compliance

Approving a PP sample approves everything attached to it. Treat these as production items, not afterthoughts.

Main label, care label, size label and country of origin — position, content and font.
Care symbols and fibre content accuracy against test reports.
Hangtags, price tickets, polybag warnings, and recycling or sustainability claims.
Carton marking, assortment ratios and packing method if a pre-pack is agreed.
Compliance documentation required for your destination market, including restricted substance testing where applicable.

Claims are where brands get into real trouble. If the garment will be marketed as recycled, moisture-wicking or UV-protective, the supporting test certificates must exist and cover the actual production lot.

Step 7 — Documenting Approval and Setting the Bulk Standard

Approval is a written act. A PP sample that is approved over chat is not approved. Your sign-off document should include:

Tech pack revision number and date referenced.
Sample type and date received.
Measurement results with pass/fail per point.
Defect list with photographs, quantities and agreed dispositions.
Color and fabric lot references.
Wash test results and shrinkage percentages.
Explicit statement of what is approved and what is conditionally approved.
Names and dates of sign-off from both buyer and factory.
Instruction that one sealed or counter-signed sample is retained by each party.

Keep two signed copies: one at the factory, one in your office. The factory copy becomes the line reference; your copy becomes the basis of any claim. Many experienced buyers also request a labelled set of reference photographs showing the approved seam, waistband and label placement on the actual approved piece.

Common Reasons PP Samples Get Rejected

Reviewing historical rejections is the fastest way to tighten your own checklist. In activewear, the same problems recur:

Substitute fabric or a different fabric lot with a visible shade or stretch difference.
Stretch recovery below the approved standard, causing sag at the knee or seat.
Waistband rolling or twisting after wear.
Transparency under stretch on light colors.
Seam slippage at the crotch and side seam under load.
Shrinkage beyond the agreed percentage after one wash.
Measurement drift in the larger sizes because grading was assumed rather than executed.
Label, care instruction or origin marking errors.
Fit that no longer matches the fit-approved sample.

A Practical Approval Decision Framework

Not every issue should stop a production run. Classify findings so you respond proportionately and keep the calendar intact.

Reject and remake: wrong fabric, wrong fit, failed seam strength, failed recovery, wrong color.
Revise and resubmit: measurement deviations, minor construction errors, label placement problems.
Approve with conditions: cosmetic issues within tolerance, documented shrinkage within agreed limits, minor packaging corrections the factory must fix before shipment.
Approve as is: no material deviation from the reference pack.

When you approve with conditions, put the conditions in writing with a deadline and make the TOP sample inspection the verification point. That way the PP sample does its job without adding a week to your lead time.

Timing: Where the PP Sample Sits in Your Calendar

Plan backwards from your delivery date. A typical activewear timeline allows three to five days for the factory to produce the PP sample after fabric and trims arrive, three to five days for shipping to you, and two to three working days for your review and sign-off. If a revision is needed, add five to seven days. Budgeting roughly two to three weeks for the PP stage protects you from the costly alternative: discovering a problem after bulk cutting has begun.

Key Takeaways

Insist the PP sample is made on the bulk line with bulk materials.
Build and number a reference pack before the sample arrives.
Measure everything, apply written tolerances, and rest the garment before measuring.
Test stretch recovery, transparency under stretch and seam strength at the high-stress points.
Wash it, re-measure it, and record the shrinkage.
Approve in writing, keep a sealed sample on both sides, and verify at TOP inspection.

A disciplined PP sample approval process is one of the cheapest quality controls available to an activewear buyer. It costs a few days and a few pages of documentation, and it prevents the two outcomes that destroy launch margins: a bulk run that cannot be sold, and a customer who never comes back. Treat the sample as the specification, and the specification as the contract.