Understanding Hill Workouts
by Jeff Godin, Ph.D., CSCS, Director of Spartan Coaching
The beauty of obstacle racing is that it exposes your weakest link. Lack upper body strength? You will pay for it on the 12 foot wall. Lack balance? You will pay for it on the balance beam. Lack hill climbing endurance? You will pay for it all-day. Spartan Race is well known for its lung crushing climbs, and quad destroying descents. According to one racer that I overheard last Saturday at the Tri State Super, “the number of climbs is ridiculous”.
The only way to beat the hill is to embrace it. Hill running increases oxygen consumption considerably. For example, an athlete running at an easy 10 min/mile pace has an estimated oxygen consumption of 36 mlO2/kg/min, where running the same speed on a 10% grade (a grade of 100% = 45 degree angle) increases oxygen consumption to 50 mlO2/kg/min. That’s almost a 40% increase in energy expenditure! Running on a flat surface, a runner only needs to produce energy for horizontal work. The extra energy needed to lift the body vertically against gravity accounts for this extra energy expenditure.
Running at an oxygen consumption of 50 mlO2/kg/min will be close to many athletes maximal oxygen consumption and certainly above the lactate threshold for all but the elite runners. This will result in an increase in muscle acidosis and increased rate of glycogen utilization. The end result is fatigue and possible glycogen depletion.
Although training will improve VO2 max and running efficiency, it will not be enough offset the increased metabolic demand of steep uphill running. The best solution is to adjust the pace or speed so the energy expenditure remains the same. For most, that will mean walking uphill at a much slower pace. This will prevent fatigue and spare glycogen and prevent bonking. Pace yourself on the hill climbs.
Walking or running uphill places unique stress on the locomotive muscles when compared to walking or running on flat ground. The change in slope puts the foot into severe dorsi flexion, stressing the gastrocnemius, soleus, and plantar fascia. The trunk also leans forward, placing more stress on the hamstrings and back extensors. A couple of small hills won’t negatively impact these muscle groups, but in the longer events where there will be 3,000 – 5,000 ft of climbing, there can be major damage to these muscles, especially in athletes who have not prepared on hills.