The short version
- 13 in long, 5.5 in across, EVA foam wrapped around a hollow core; firm, and light at roughly 1.1 to 1.4 lb depending on which line of the listing you read.
- $39.95 on Sep 30, 2026 for the Black 13 in roller, shipped and sold by Amazon.com, 30-day refund or replacement shown; the brand's own store listed it at $39.99 the same day.
- Pooled trials show small, short-lived effects: a bit more range of motion right after rolling, and somewhat less soreness in the day or two after a hard session. Nothing more than that is well supported.
Not a workout tool.
Nothing to eat here.
A few minutes after a session, or on an easy day, on calves, thighs and upper back.
What the spec shows
We read the Amazon listing for the Black 13 in roller (ASIN B0040EGNIU, model 15920) and TriggerPoint's own GRID 1.0 product page on Sep 30, 2026. Two numbers differ between the two, and the table says which is which.
| Spec | Value | What to know |
|---|---|---|
| Length | 13 in (33 cm) | Per the brand. Long enough for one thigh or calf at a time, or the upper back if you keep your elbows in. Not a full-width roller for lying across. |
| Diameter | 5.5 in | Per the brand. The Amazon description text says "five inches"; the brand's figure is the one we use. |
| Weight | About 1.1 to 1.4 lb | Amazon's spec table says 1.1 lb (0.5 kg); the listing's own FAQ text says 1.4 lb. Either way it is light enough to leave by the mat or throw in a bag. |
| Construction | EVA foam over a hollow core | A rigid hollow tube with a layer of EVA foam moulded around it. The brand says the hollow core helps the roller keep its shape with repeated use. |
| Surface | Three zone patterns | The brand describes flat areas, tubular ridges and dense nodules; the Amazon listing calls the layout "Distrodensity Zones". In practice: flatter areas and bumpier areas, chosen by where you put the roller under you. |
| Firmness | "Extra Firm" (Amazon field) | This is a hard roller. If you have only used soft closed-cell foam before, expect a noticeably sharper feel, especially on the ridged zones. |
| Weight capacity | 300 lb (brand) / 500 lb (listing) | TriggerPoint's site says the core supports up to 300 lb; the Amazon listing copy says 500 lb. We use the lower figure. |
| Warranty | 1 year, limited | Against defects in materials and workmanship, per both the brand and the listing. |
| Care | Mild soap and water | Brand instruction. The listing's directions say a damp cloth, then air-dry. EVA is closed-cell, so it does not soak up sweat. |
| Colors | Black priced here | The same listing offers Teal, Mint, Tan, Midnight, Grey Camo, Pink and Camo 13 in rollers, plus six-packs, at their own prices. |
How it holds up in use
The build first. The hollow-core design is the reason this roller costs more than a plain foam log: solid foam rollers soften and go out of round with use, while a rigid core with a foam skin keeps the same feel. The listing has been on Amazon since 2009, which says something about the design if not about any one unit. The 13 in length is a deliberate compromise. It stores easily and travels, and it is fine for a calf, a thigh or the back of a shoulder; it is short for rolling both thighs at once or for lying across it sideways, which is what a 26 in or 36 in roller is for. The surface pattern gives you a choice of intensity by turning the roller, which is genuinely useful when the ridged side is too much on a sore day.
Now the evidence, kept modest, because the marketing around foam rolling is not. A 2019 meta-analysis in Frontiers in Physiology pooled 21 studies and found that rolling before exercise produced small improvements in flexibility (about 4 percent) and in sprint performance (under 1 percent), with negligible effects on jump and strength; rolling after exercise slightly reduced how sore people said they felt and slightly softened the drop in performance that follows a hard session. The authors' own summary was that the effects are "rather minor and partly negligible" [1]. A 2022 review in Sports Medicine looked at rolling as a repeated practice rather than a single session: across 11 trials and 290 mostly young participants, several weeks of regular rolling produced a moderate increase in joint range of motion, more so when the program ran longer than four weeks, and the effect showed up for hamstrings and quadriceps but not for the calves and ankle [2]. A 2024 pooled analysis of 16 randomized trials found that rolling after exercise was linked to lower soreness ratings at 24 to 72 hours, with a small effect immediately afterwards [3]. And a 2024 review in the Journal of Sport and Health Science is worth knowing about as a corrective: across 38 studies, stretching and foam rolling were no better than a range of other warm-up activities, such as ones that simply warm the muscles, at producing a short-term gain in range of motion [4].
Put together, that supports a limited and honest use: a few minutes on the muscles you worked, after a session or the next day, for a bit more range of motion and a bit less of that stiff, tender feeling. The brand's listing talks about "deep tissue" massage, "knots" and improved circulation; those are the seller's words, not findings from the reviews above, and we do not repeat them as claims.
This is a hard roller, and rolling means putting body weight through it. Some people should not, or should ask first: anyone with a recent injury or a fresh strain, anyone with a clotting or bleeding concern or who bruises very easily, anyone who is pregnant, and anyone who has been told by a clinician to avoid pressure on a specific area. Nobody should roll directly on the lower back, over joints, or on bone. Sharp pain is a stop signal, not something to push through. If in doubt, ask a clinician before starting.
How to fit it into a simple week
This is a sequence, not a promise. It is written for a healthy adult who already moves a little.
Pick two or three areas, not the whole body
After the 20-minute routine or on an easy day, choose the muscles you actually used: calves, the front and back of the thighs, the upper back. Start on the flatter areas of the roller.
Thirty to sixty seconds per area, slowly
Slow passes, breathing normally, supporting some of your weight on your hands or the other leg. If a spot is sharp rather than dull, ease off or move on. Three to five minutes total is plenty.
Keep it off the spine and the joints
Roll the muscle beside the shin, not the shin; the thigh, not the knee; the mid and upper back with your hands behind your head, never the lower back.
Give it more than four weeks before judging it
The range-of-motion evidence favors regular use over a single session. Two or three short sessions a week for a month is a fair trial; if you notice nothing by then, you are allowed to stop.
Wipe it and leave it by the mat
A damp cloth, then air dry. A roller that lives in a cupboard does not get used; one that lives next to the mat does.
Price and where it is sold
On Sep 30, 2026 the Black 13 in GRID 1.0 was $39.95 on Amazon, shipped from and sold by Amazon.com, with "FREE 30-day refund/replacement" shown on the listing (listing). TriggerPoint's own site listed the same roller at $39.99 the same day, so the two prices were within a few cents. Other colors on the Amazon listing carried their own prices. Prices change; this figure is what we saw on that date only.
Who should look elsewhere
- Anyone who wants to roll both thighs at once, or lie across a roller for the upper back, should look at the longer GRID 2.0 (26 in) rather than this 13 in size.
- People who have found firm rollers too intense should look at a softer, solid foam roller; this one is listed as extra firm and the ridged zones are sharper still.
- Anyone heavier than the brand's stated 300 lb capacity should take the listing's 500 lb figure with caution and choose a roller whose maker states a higher limit clearly.
- If you want targeted, hand-held pressure rather than rolling on the floor, a percussion massager is a different tool with its own trade-offs (see the RENPHO entry).
- Anyone in the groups named in the caution above, or unsure whether rolling suits them, should ask a clinician first.
Sources
- Wiewelhove T et al. Meta-analysis of the effects of foam rolling on performance and recovery (21 studies; pre- and post-exercise rolling). Frontiers in Physiology, 2019 (PMID 31024339). PubMed, DOI
- Konrad A et al. Systematic review and meta-analysis of foam-rolling training over several weeks on joint range of motion (11 trials, 290 participants). Sports Medicine, 2022 (PMID 35616852). PubMed, DOI
- Zhou J et al. Systematic review and meta-analysis of foam rolling and muscle soreness after exercise (16 randomized trials, 515 participants). Journal of Bodywork and Movement Therapies, 2024 (PMID 39593540). PubMed, DOI
- Warneke K et al. Systematic review with meta-analysis comparing stretching and foam rolling with other warm-up activities for short-term flexibility and stiffness (38 studies). Journal of Sport and Health Science, 2024 (PMID 38244921). PubMed, DOI
- TriggerPoint. GRID 1.0 Foam Roller product page (13 in x 5.5 in, EVA foam over hollow core, 300 lb capacity, one-year warranty, care, brand-site price). Accessed Sep 30, 2026. link
- Amazon.com. Product listing "TriggerPoint Grid 1.0 Foam Roller", Black, 13 in, ASIN B0040EGNIU, model 15920: spec table (1.1 lb, extra firm), description (500 lb, five-inch diameter), warranty text, care text, price, seller and return window. Accessed Sep 30, 2026.
This entry is educational and is not medical advice. Ask a qualified clinician before starting any supplement or new exercise routine, especially if you are pregnant, nursing, have an existing condition, or take medication.