Adidas Ultraboost 5X vs Mizuno Wave Rider 29:
Which to Choose

Start with what's genuinely the same: both are neutral trainers with wide, planted platforms, no medial post, no propulsion plate, and comparable cushioning depth, so neither is meaningfully more "stable" than the other in practice. The real separators are foam, fit, weight, and range. The Ultraboost's Boost TPU midsole is the softer, bouncier of the two — a noticeably springy, rebounding feel underfoot — but the foam is dense and the shoe is heavier (around 272g in a men's sample versus roughly 258g for the Wave Rider 29), so that energy comes with a slightly sluggish feel when you try to lift the pace. Mizuno's Enerzy foam is firmer and less pillowy but transitions more crisply; it rewards a steady rhythm and feels composed slowing down, and the lighter build gives it a modestly quicker effective ceiling (its sharp-end zone sits near 4:45–5:15 min/km, against roughly 5:30 min/km for the Ultraboost before the weight starts to bite). The upper is the other decisive difference: the Ultraboost uses a laceless Primeknit knit that slips on and hugs like a sock but runs warm on hot days, while the Wave Rider's laced engineered mesh is more breathable and lets you dial in a secure, adjustable fit. Both drops are effectively the same traditional ~10mm heel-forward geometry, so neither will feel radically different in transition. Finally, range: the Ultraboost 5X peaks at 10K and half, whereas the Wave Rider 29 is comfortable stretching all the way to a full marathon, with the half as its sweet spot.