The impact of pole use on vertical cost of transport and foot force during uphill treadmill walking before and after a simulated trail running competition

Purpose: Trail running poles are widely used among trail runners but their effects on cost of transport and biomechanics under fatigued conditions remains understudied. This study aimed to evaluate the effects of pole use on the walking vertical cost of transport (CoTvert) and foot force (FF) before and after a simulated trail running competition (STRC). Methods: Sixteen trail runners (V˙O2: 61.0 ± 8.3 ml/kg/min; ITRA performance index: 634 ± 107 points) performed walking trials with (PW) and without poles (CW) on an incline treadmill (18.6 degrees) before (PRE) and after (POST) a STRC. The course covered 31.2 km with 2086 m of elevation gain and was completed under race-simulated conditions. CoTvert and FF were measured using instrumented insoles, and axial pole force was recorded during PW. Results: The STRC was completed in 4:25:33 ± 0:39:51 (hh:mm:ss) at an average heart rate (HR) of 81.4 ± 3.8% of HRmax. Walking CoTvert showed significant time and condition effects, with higher values without poles at POST (+ 2.50 ± 2.62%, p = 0.0183). Rating of perceived exertion (RPE) was lower with poles at both PRE and POST (p = 0.0022 and p = 0.0187, respectively). FF was significantly lower with poles at PRE (p = 0.0140) and POST (p < 0.0001). Poling force decreased at POST compared to PRE (p = 0.0026). Conclusions: The main findings are that (1) CoTvert increases after STRC; (2) walking CoTvert and FF are lower with pole use and (3) upper limb force decreases at POST. These results support the use of poles in long-lasting events to reduce CoT, redistribute workload and possibly mitigate the fatigue effects.