Sew Can Do: Basic T-Shirt to Athletic Shirt in 5 Minutes!

Got a t-shirt that's a bit too small or getting snug? Want some sporty clothing, but don't want to pay the hefty athletic wear price tag? Sew in your own sporty side panels to add room, stretch and high-end sport fabric features to ordinary t-shirts!

You'll Need:

- 1/8yd of Athletic/Performance knit fabric* (this will make enough for several shirts)

- T-shirt

- Sewing Machine & Notions (pins, ruler, marking pen/chalk, twin needle, thread, scissors/rotary cutter)

* I used Athletic/Performance fabric for my panels. It wicks away perspiration, inhibits odor, often has UV sun protection and a 4-way stretch, so it really adds the endurance of athletic wear in all the right places. It's not always easy to find, so good alternatives are spandex, swimsuit fabric or jersey.

**Sewing Knits Tip: Refer to my post on Sewing Knits Without A Serger for more info on the stitches used here.

The length on this t-shirt was still ok, but after 2 years of wear it was too snug under the arms for my 6yr old to wear comfortably. Here's how I made it fit like new again:

Turn t-shirt inside out and trim off 1/8inch off the seam to open the sides and measure the length from sleeve cuff to bottom hem:

Cut two side panels from the Pellon Sport fabric that are 1 inch longer than the shirt to hem measurement and at least 3 and 1/2 inches wide (wider if desired - it's up to you!). Trim one end on an angle inward on either side so that it narrows to 3 inches wide as shown:

Make a 1/2 inch hem on the narrowed end and sew in place with a twin needle:

With right sides of the fabrics facing, pin the panel to the raw edges of one of the shirt sides, lining up the hemmed end with the shirt sleeve. Stitch each length side using a knit stitch and a 3/8 inch seam allowance. Turn shirt right side out and fold under the bottom edge and sew the hem with twin needle. Repeat with the remaining side of shirt.