With no sign of the present heatwave abating we pause to admire the stamina and stoicism of endurance runners in the runABC South area this weekend. A packed fixture list for the first full weekend of July includes some extraordinary long distance events, where simply reaching the finish line will be more important than finishing times.
Some coaches reckon the stress of running in high heat and humidity can add 20 bpm to our average exercise heart rate, forcing us to slow down between 30sec and 90sec per mile pace in our usual running speed. A common calculation is to add 1.5% to 3% to your expected time for every 5C above the 'perfect' running temperature of 12-13C. That equates to an extra 3-6 minutes for a 3:30 marathon for each 5C increment.
These averages are magnified when fatigue is factored in and can be significantly higher in long distance races, especially if rough and hilly terrain is a further consideration. Despite all this, competitor numbers in ultra-distance events are on the increase and this is testament to athletes' outstanding conditioning and superb support out on the course.
Saturday (7 July) will see a few hundred brave souls tackle the Serpent Trail 100K ultra in the South Downs National Park from Haslemere to Petersfield. The full route passes through greensand hills, lowland heath and river meanders of Sussex, Surrey and Hampshire. There are 50K, half marathon and 10K options for those whose endurance is still work in action.
Also on Saturday is the Ham and Lyme 100K, taking in the stunning Liberty Trail, which runs from Ham Hill Country Park in Somerset to Lyme Regis in Dorset. Competitors in this race will be following the footsteps of the villagers who walked down to the sea to join the Monmouth Rebellion in 1685.
An even longer and arguably tougher challenge on Saturday and Sunday is the Round the Island, a 70-mile ultra-marathon following the superb Coastal Path round the Isle of Wight. The place will be buzzing as the event coincides with the annual Cowes Weekend, with over 2,000 yachts congregating for their own Round the Island Yacht Race.
Sunday's action includes the North Downs Way Marathon from Reigate Hill car park to the Boxhill lookout post (one lap for the half marathon option) with a unique horse brass medal.