There have been many debates about whether or not using poles are actually beneficial for climbing in trail races. In Europe it is very common for athletes to use them perhaps because of a history of using poles in the mountains and perhaps because of athletes familiarity of using them during winter sports. This study aimed to:
compare the energy expenditure during uphill walking with (PW) and without (W) poles at different slopes. [To do this] fourteen mountain running athletes walked on a treadmill in two conditions (PW and W) for 5 min at seven different angles (10.1°, 15.5°, 19.8°, 25.4°, 29.8°, 35.5° and 38.9°).
The study found that using poles was only slightly more economical than not using them, however, the RPE of using poles was much lower than not using them. Based on this, the authors recommended that:
PW suggests that poles may delay fatigue effects during a prolonged effort. We advocate for the use of poles during steep uphill walking, although the energetic savings are small.
PRACTICAL TAKE AWAY - poles can provide an advantage when racing on steep terrain especially in longer races where the RPE of climbing is reduced.
RACING: The Metabolic Costs of Walking and Running Up a 30-degree Incline: Implications for Vertical Kilometer Foot Races
When to run and when to walk on steep terrains is a tough question to answer and in races we see many different athletes at all levels choosing different strategies. This study aimed to quantify the cost of either modality to help inform the training and strategy of vertical kilometer racers.
The results of the study showed that:
On a 30° incline, metabolic power increases linearly with velocity. At speeds slower than 0.7 ms-1, walking requires less metabolic power than running (W kg-1) suggesting most VK racers should walk rather than run.
PRACTICAL TAKE AWAY - on very steep terrain most athletes should walk
1: Effects of an Uphill Marathon on Running Mechanics and Lower-Limb Muscle Fatigue
2: Effects of the Etna Uphill Ultramarathon on Energy Cost and Mechanics of Running
These two studies are quite similar so I've linked the two together. They are both looking to understand the impact of uphill running on energy and mechanics:
1: To investigate the effects of an uphill marathon (43 km, 3063-m elevation gain) on running mechanics and neuromuscular fatigue in lower-limb muscles.
2: To investigate the effects of an extreme uphill marathon on the mechanical parameters that are likely to affect the energy cost of running (Cr).
The results were similar and showed that lower limb strength is a key component of mechanics, cost of running, and therefore performance in uphill races:
1: Greater maximal mechanical power was related with smaller changes in running mechanics induced by fatigue. Thus, lower-limb power training could improve running performance in uphill marathons.
2: Lower Cr was related with better performance, and athletes characterized by the greater Pmax [maximal explosive power of the lower limb] showed lower increases in Cr during the race.
PRACTICAL TAKE AWAY - "specific power training of the lower limbs may lead to better performance in ultraendurance running competition."