Quick answer
Choosing running shorts comes down to personal comfort, your running style, and the conditions you run in. Focus on a secure but comfortable waistband fit, select a length that feels right for your stride, and prioritize features like moisture-wicking fabric and a supportive liner.
Figuring out how to choose running shorts is a key step in building a comfortable running wardrobe. The right pair can feel like a second skin, while the wrong one can lead to distraction and chafing. This guide breaks down the essentials of fit, length, and features to help you find shorts that support every mile.
The Foundation: Getting the Fit Right
A good fit is non-negotiable. Running shorts should stay in place without restricting your movement or requiring constant adjustment. The two primary areas to focus on are the waistband and the overall cut.
The waistband should sit comfortably on your hips or waist without digging in. Many running shorts use an internal drawcord for a customizable fit. The fabric through the hips and thighs should allow for a full range of motion—if you can’t comfortably take a long stride or high knee, the shorts are too tight. Conversely, excessive fabric that bunches or flaps can be irritating. For a broader look at running apparel, see our running clothing guide.
Understanding Inseam Length
Inseam length is a major comfort and style preference. It’s measured from the crotch seam down the inner leg to the hem.
- 1-3 inch inseams: Often called “split shorts” or “racer shorts,” these are very short and lightweight, offering maximum freedom of movement. They are popular among competitive runners.
- 5-7 inch inseams: This is a versatile, mid-length option that provides good coverage and is a common choice for daily training.
- 7+ inch inseams: These longer shorts, sometimes reaching the knee, offer more coverage and can feel more secure for some runners. They are also a common choice for trail running to protect legs from brush.
How to Choose Running Shorts by Length and Style
Beyond basic inseam measurement, shorts come in different constructions that affect feel and performance.
| Style | Description | Best For |
|---|---|---|
| Standard Brief-Liner Shorts | Feature a built-in, brief-style liner (like lightweight underwear) for support and to minimize chafing. The outer shell is often loose. | Most road running; hot weather; runners who prefer a traditional feel. |
| 2-in-1 or Liner Shorts | Have a tight, compression-style inner short attached to a looser outer short. Provides muscle support and eliminates inner-thigh chafing. | Long runs; runners who want compression benefits; those prone to chafing. |
| Split Shorts | Feature a high side slit (often with a brief liner) for an unrestricted stride. They are typically very lightweight. | Speedwork; racing; runners who prioritize a completely free range of motion. |
| Compression Shorts | Form-fitting, stretchy shorts worn alone. They offer muscle support and reduce skin-on-skin friction. | Under layers; cold weather base layers; recovery; some prefer them for all running. |
Key Features to Consider
Modern running shorts come with various features that add functionality. Think about what you need for your typical runs.
What to look for
- The Liner: This is critical. A good, soft, seamless liner provides support and prevents chafing. Some are treated with anti-microbial properties. You can choose to wear your own underwear, but the liner is designed to be worn without.
- Pockets: Essential for carrying fuel, keys, or a phone. Look for secure pockets: a zippered back pocket, a secure waistband pocket, or side pockets with zippers or tight openings. For long runs or trail running, more pockets are better.
- Material: Look for lightweight, synthetic fabrics like polyester or nylon that wick sweat away from your skin quickly. This keeps you drier and more comfortable. Mesh panels add ventilation. Like with running socks, moisture management is key.
- Reflective Details: For safety during low-light runs, reflective logos or piping help you stay visible.
Your other gear choices matter, too. The right hat or visor protects you from the sun, while a well-chosen jacket handles wind and rain, allowing your shorts to focus on breathability.
Safety
In extreme heat or cold, clothing is your first layer of protection. In hot weather, light-colored, moisture-wicking shorts help with temperature regulation. In cold weather, compression shorts can serve as a base layer under tights. Always check the weather and dress appropriately. For official guidance on exercising in heat or cold, see resources from the National Weather Service.
FAQ
Should running shorts be tight or loose?
It depends on the style and your preference. The waistband should be snug enough to stay up without a belt. The leg fabric can range from very loose (standard brief-liner shorts) to form-fitting (compression shorts). The key is that they don’t restrict your natural running stride. 2-in-1 shorts offer a combination: a tight inner layer with a loose outer layer.
What is the purpose of the liner in running shorts?
The built-in liner provides support, reduces friction between your thighs, and wicks moisture. It’s designed to be worn without additional underwear, as extra layers can create seams that lead to chafing. If the liner is uncomfortable, some runners cut it out and wear their preferred compression shorts underneath.
How many pockets do I need?
Consider your typical run. For short road runs, a single small key pocket may suffice. For long runs or trail running where you need to carry gels, a phone, or an extra layer, look for multiple secure pockets, preferably with zippers to prevent items from bouncing out.
Can I wear the same shorts in winter and summer?
You can, but you may be more comfortable with seasonal choices. Lightweight, breathable shorts with lots of mesh are ideal for summer. In winter, a slightly heavier fabric or a compression short worn as a base layer under running tights or pants is a better choice for warmth. Explore all your running clothing options for different seasons.
How do I prevent chafing from running shorts?
Chafing is often caused by seams, a poor-fitting liner, or moisture. Ensure the shorts fit well without rough seams in high-friction areas. A quality liner or a 2-in-1 design can help. Using an anti-chafe balm on thighs and other sensitive areas is also highly effective for prevention.
References
- Manufacturer manuals and specification sheets: For details on material composition, care, and feature specifications.
- American College of Sports Medicine (ACSM): General guidance on sports performance and apparel. https://acsm.org/
- National Weather Service: For safety information on exercising in heat and cold. https://www.weather.gov/safety/heat, https://www.weather.gov/safety/cold
