The Altra Lone Peak 2.5 is, quite simply, a phenomenal long distance trail running shoe.  Although Altra is known for building shoes with a wide toe box and zero drop, the Lone Peak offers much more than these signature features. The cushioning and protection are appropriate for a long distance shoe without being excessive (and hence too heavy), and the outsole is effective on nearly every surface imaginable. The new midsole material also provides some energy return without the stiffness that can become tiring after several hours. Where the Lone Peak really shines is its handling and agility. The Lone Peak has an incredibly intuitive feel, which becomes extremely helpful when running technical terrain while fatigued, such as during the latter stages of a long run or race. 

The main limitation of the Lone Peak is its speed and turnover.  Although the responsiveness of the midsole is improved over previous versions of the shoe, the Lone Peak is not a shoe designed for faster running. While this does not necessarily detract from its long distance capabilities, it does make the Lone Peak less versatile than some shoes in this weight class.

The Lone Peak will appeal to runners who want a trail shoe for long runs, rugged terrain, and racing at the marathon and ultra-marathon distances.  The Lone Peak is probably not the best choice for runners who need a high level of cushioning, or who want a shoe that can handle faster running more effectively. Also note that runners not used to zero-drop shoes may need some time for their lower legs to adjust.

Comfort
The upper of the Lone Peak 2.5 is constructed of a soft and slightly stretchy mesh-like fabric that provides an extremely comfortable fit. The lack of any rigid overlay material also helps to avoid hot spots. Underfoot, the new midsole material has a springier feel to it, and the shoe remains comfortable even after several hours of running. Breathability was not an issue during testing. The Lone Peak is not, however, a super plush shoe, and the amount of cushioning is best described as moderate.

Speed
Speed and turnover are clearly the weak point of the Lone Peak 2.5. This is in part simply a consequence of the overall weight of the shoe, but is exacerbated by the zero-drop platform. The Lone Peak 2.5 also has a slight weight imbalance between the upper and lower, which gives it a bottom-heavy feel during fast running. 

Security of Fit
Although the Lone Peak 2.5 has a wide toe box, the side contours of the shoe do not open up too fast, so that the fit from heel through the midfoot stays secure. However, the lockdown of the revised upper in the forefoot area is somewhat less effective and requires more attention to lacing. This is not necessarily problematic, but will likely be noticeable to runners used to the Lone Peak 2.0. 

Agility
The Lone Peak is without question one of the most intuitive handling trail shoes in its weight class.  The zero-drop platform keeps the heel out of the way despite the 25mm overall stack height, and the wide forefoot provides ample ground contact area. If there’s a weakness in this area, it’s that the upper/lower weight imbalance slightly inhibits foot pickup. 

Responsiveness
The responsiveness of the Lone Peak 2.5 is significantly improved over previous versions, and the new midsole provides an excellent balance between cushioning and energy return. This is most noticeable as a touch of snappiness while running hard uphill. The responsiveness also helps compensate for the lack of natural speed on flatter surfaces.