Lululemon Speed Up 2.5 vs. 4: Which size is right for you?

The Lululemon Speed Up 2.5" and 4" shorts are both designed for running, but the 1.5-inch difference in length tailors them to distinct preferences and needs. The 2.5" version offers a minimal, lightweight feel perfect for race day or hot weather, prioritizing speed and freedom of movement above all. In contrast, the 4" model provides more modest coverage, making it a more versatile and secure-feeling option for trail runs, gym sessions, and daily errands without sacrificing performance.

Here’s everything you need to know to pick the right Lululemon inseam for your runs and workouts.

Lululemon Speed Up High-Rise Lined Short 2.5"

The Speed Up 2.5" is the shortest version in this running lineup, engineered for those who want as little fabric as possible for maximum agility and breathability. Its lightweight design and minimal coverage make it a favorite among competitive runners, sprinters, and anyone working out in high heat who finds extra material distracting.

• What it is: A high-rise, lined running short with a 2.5-inch inseam, designed for a lightweight and freeing feel.
• Key features: High-rise waist with a continuous adjustable drawcord, multiple waistband pockets including a secure back zipper pocket, a lightweight built-in liner for coverage, and reflective details.
• Price: ~$68 USD
• Materials/Construction: Made with lightweight, four-way stretch Swift fabric that is sweat-wicking and quick-drying. The liner and waistband are made of soft, supportive Light Luxtreme® fabric.
• Sizing/Fit: True to size with a relaxed fit through the legs that allows for a full range of motion. The high-rise waist offers support and coverage around the midsection.
• Pros: Excellent breathability for hot weather, incredible freedom of movement, minimal and lightweight feel, ample pocket storage for a small short.
• Cons: Coverage is very minimal and may not be comfortable for everyone, can feel revealing during squats or stretching, may ride up more than the longer version.

This short is ideal for seasoned runners focused on speed, those who prefer minimal fabric during intense workouts, or petite individuals for whom the 2.5" inseam provides just the right amount of coverage.

Shop this product: shop.lululemon.com/p/women-shorts/Speed-Up-Short-HR-2-5

Lululemon Speed Up High-Rise Lined Short 4"

The Speed Up 4" offers a modest increase in length that translates to a significant difference in coverage and versatility. While still a serious performance short, the extra 1.5 inches provide more security and make it suitable for a wider range of activities beyond the running track, from gym workouts to casual neighborhood walks.

• What it is: A high-rise, lined running short with a 4-inch inseam that provides a balance of performance and coverage.
• Key features: Shares the same key features as the 2.5" version, including the high-rise waist, continuous drawcord, gel pockets in the waistband, zippered back pocket, built-in liner, and reflective details.
• Price: ~$68 USD
• Materials/Construction: The same lightweight, sweat-wicking Swift fabric as its shorter counterpart, with a smooth Light Luxtreme® fabric waistband and liner.
• Sizing/Fit: Also fits true to size with a relaxed leg opening. The longer inseam provides more coverage down the thigh, reducing concerns about exposure during movements.
• Pros: More versatile for various activities, provides greater coverage and a more secure feel, less prone to riding up during long runs, suitable for a wider range of body types.
• Cons: Slightly less breezy feeling than the 2.5" version in very hot conditions, the extra fabric might feel like a minor hindrance to runners who prefer absolute minimalism.

This length is a great all-around choice for runners who want a bit more modesty, taller individuals, or those looking for one pair of shorts that can handle gym sessions, long runs, and errands equally well.

Shop this product: shop.lululemon.com/p/women-shorts/Speed-Up-Short-HR-4

Lululemon Speed Up 2.5" vs. 4" Comparison

Coverage & Length

The most important difference lies in the 1.5-inch inseam variation. The Speed Up 2.5" short is explicitly minimal. On an average-height person, it provides just enough coverage for running, but deeper movements like lunges or squats can feel revealing. It's often favored by petite women (5'4" and under), as the length is proportional to their frame, or by runners who simply are not concerned with showing more leg.

The Speed Up 4" short feels much more substantial. That extra length provides significantly more thigh coverage, building confidence during cross-training exercises or while bending over. For taller individuals, this length often hits at a more comfortable and flattering spot on the upper thigh, whereas the 2.5" might feel like a brief.

Fit & Comfort

Both models share the same comfortable high-rise and smooth Light Luxtreme® waistband with a continuous drawcord, ensuring a secure, non-slip fit. Their relaxed leg design prevents chafing and promotes airflow. The primary comfort difference is psychological and activity-based.

Some runners find the minimal fabric of the 2.5" version more comfortable because it feels lighter and less restrictive. However, others dislike having to adjust shorts that ride up. While both lengths can move, the 4" version is generally less prone to significant ride-up due to its added length and weight.

Versatility

The 4" Speed Up short is the clear winner in versatility. Its moderate coverage makes it appropriate for a wider array of settings. You can easily go from a 10k run to the grocery store or a coffee shop without feeling underdressed. It's also a better choice for gym environments where you might be doing a mix of cardio and floor exercises.

The 2.5" Speed Up short is a more specialized piece of gear. It excels during solo runs, track workouts, and race days where every gram and every inch of fabric counts toward your comfort and speed. It's less ideal for casual wear or multifaceted workouts purely based on its minimal coverage.

Price & Value

Both the 2.5" and 4" versions of the Speed Up shorts are priced identically at around $68. Because there is no cost difference, the value proposition is determined entirely by which short best fits in your wardrobe and life. The better value is the one you will reach for most often and feel most comfortable wearing. For most people, the 4" short provides more value due to its enhanced versatility.

Which One Should You Choose?

While both shorts are excellent running gear, your choice depends entirely on your priorities for coverage, body type, and primary activities.

Choose the Speed Up 2.5" if:

• You prioritize maximum cooling and a "barely there" feel for running.
• You are primarily using them for intense runs, races, or track workouts in the heat.
• You are petite, and shorter inseams tend to fit your proportions better.
• You aren't concerned with showing more leg and prefer minimal fabric.

Choose the Speed Up 4" if:

• You want a versatile short for running, cross-training, and casual wear.
• You are taller, and the extra length provides more comfortable coverage.
• You prefer more security and modesty during dynamic movements like squats and lunges.
• You are concerned about shorts riding up and want a length that tends to stay put better.

Frequently Asked Questions

What’s the main difference between the Speed Up 2.5" and 4" shorts?

The defining difference is the inseam length. The 2.5" short offers minimal coverage suited for speed and hot weather, while the 4" short provides moderate coverage for more versatility and a secure feel during various activities.

Do the Speed Up shorts have a liner?

Yes, both the 2.5" and 4" versions of the Lululemon Speed Up shorts come with a built-in, lightweight brief liner made from sweat-wicking Light Luxtreme® fabric for comfort and coverage.

Do these shorts have pockets?

Absolutely. Both lengths of the Speed Up short are known for their great storage. They feature easy-access gel pockets in the waistband and a secure zippered pocket in the back that is large enough for a key, card, or sometimes a smaller phone.

Do Lululemon Speed Up shorts ride up when running?

Any short can ride up slightly depending on body shape and stride, but the 4" version is generally more stable and less prone to riding up compared to the 2.5" version. The minimal fabric of the 2.5" can move more freely, leading to some ride-up for certain runners.

Are the Speed Up shorts true to size?

Yes, most people find that the Speed Up shorts fit true to size. They are designed to have a relaxed fit through the legs, so stick to your usual Lululemon size for the best fit. The high-rise waistband provides secure coverage for your midsection.

Which length is better for running vs. weightlifting?

The 2.5" short is often preferred by serious runners for minimal distraction. The 4" short is much better for weightlifting or gym sessions because the extra coverage provides more security and comfort during squats, deadlifts, and stretches.

What material are the shorts made of?

Lululemon Speed Up shorts are made from four-way stretch Swift fabric, which is lightweight, sweat-wicking, and fast-drying. The comfortable liner and wide waistband are made of their Light Luxtreme® fabric.

How do Speed Up shorts compare to Hotty Hot shorts?

Speed Up shorts generally have a slightly more athletic, less flared leg opening than Hotty Hot shorts. The waistband on the Speed Up is also different, offering connected pockets and a continuous drawcord. Many runners prefer the Speed Up for its pocket system and more streamlined fit, while the Hotty Hot is popular for both training and casual athleisure looks due to its flouncier design.