adidas Ultra Boost 21 Trainers - Black - Blue - 8.5
Not Available
Currently unavailable
Currently out of stock
This product is not available at the moment. Check back later.
Product Information
Full details
The adidas Ultra Boost 21 trainers are engineered for adult male runners seeking a balance of high-energy return and consistent comfort during daily training or long-distance runs. Featuring advanced cushioning technology, these trainers help minimize fatigue through superior impact absorption. While they offer excellent performance, users should note that the polyester construction requires careful cleaning to maintain the structural integrity and aesthetic finish of the black and blue colourway.
All features
| Age Group | adult |
|---|---|
| Colour | Black |
| Gender | Male |
| Material | Polyester |
| Shoe Size UK | 8.5 |
| Accent Colour | Blue |
| Shoe Type | Trainers |
| Series | Ultra Boost 21 |
| Model Part Number | S23867-85 |
| Brand | adidas |
Extended Product Information
FAQs
Are these shoes suitable for wet weather?
While the polyester upper is durable, the shoes are not waterproof. They provide good traction on damp roads, but avoid deep puddles.
Can I put these in the washing machine?
It is not recommended. Machine washing can damage the adhesive and the responsive foam structure. Spot clean with a damp cloth instead.
Are these true to size?
The Ultra Boost 21 generally fits true to size, though some runners prefer a half-size larger to accommodate natural foot swelling during long runs.
What is the primary material used?
This specific variant uses high-quality polyester for the upper, chosen for its balance of breathability and durability.
Are these good for flat feet?
The series is designed to be neutral; if you require specific orthotic support, you can remove the existing insole and replace it with your own.
Troubleshooting
Feeling of tightness in the midfoot area
Adjust the lacing pattern to be slightly looser across the midfoot, or ensure your socks are of a thinner athletic gauge.
Slippage at the heel
Try a runner's loop (heel lock) lacing technique to secure the ankle collar more firmly against your heel.
Pros and Cons
Pros
- High energy return for efficient running
- Sleek and versatile black and blue aesthetic
- Excellent cushioning for joint protection
- Reliable support for long-distance training
Cons
- Polyester upper may require frequent spot cleaning
- Less suitable for rugged trail running compared to specialized gear
- Requires a break-in period for optimal fit
Setup, Compatibility & Care
To ensure the longevity of your adidas Ultra Boost 21 trainers, follow these guidelines:
- Break-in Period: Wear the shoes for shorter walks before attempting full-distance runs to allow the foam and upper materials to conform to your foot shape.
- Cleaning: Use a soft-bristled brush to remove dry mud or dirt. For deeper cleaning, use a mild soap and a damp cloth; avoid submerging the trainers in water or using harsh chemicals, as this may degrade the polyester weave.
- Storage: Keep your trainers in a cool, dry area away from direct sunlight to prevent the cushioning materials from hardening or discoloring.
- Rotation: If running daily, consider alternating with a second pair to allow the foam to fully recover its shape between sessions.