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The Interval - Issue 5

Summer Solstice Training

6/20/2025

The Interval - Issue 5

Warm-Up

Welcome to Issue 5 of The Interval

The weather seems to be turning for the better, though as runners know, we can never quite trust it. Just last week I found myself in a running vest one day and reaching for my waterproof jacket the next, such is the unpredictable nature of British running conditions.

I’ve been nursing a slight niggle in my left hamstring recently, which has meant resting this week. It’s always frustrating when your body forces you to dial back the intensity, but I’m hopeful that next week will see me back to intervals or hill sessions. As always, I’ll be listening to my body and letting that guide my training decisions.

In this week’s issue, we cover three essential topics for the summer running season ahead. First, we explore the Longest Day Challenge, how to plan and execute your summer solstice long run to make the most of those extended daylight hours. We then dive into Mastering Variable Weather, sharing strategies for adapting your gear and mindset when conditions change mid-run (as they inevitably do). Finally, we tackle Summer Hydration, covering the fundamentals of staying properly fuelled and hydrated as temperatures rise and training intensifies.

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First Interval

Longest Day Challenge - Planning Your Summer Solstice Long Run

The summer solstice gives UK runners nearly 17 hours of daylight (4:30 AM to 9:30 PM), your annual invitation to attempt something extraordinary. This is the time to tackle routes you’ve been saving for “someday” and embrace adventures that simply aren’t possible during winter’s short days.

Adventure Run Opportunities:

  • Point-to-point routes using public transport for return
  • Sunrise-to-sunset challenges across varied terrain
  • Multi-peak adventures with time for navigation and photos
  • Coast-to-coast crossings taking advantage of extended safety window
  • Routes through remote areas normally too risky in limited daylight

Safety for Extended Solo Adventures: Essential kit: fully charged phone with offline maps, GPS watch with breadcrumb navigation, lightweight waterproof layer, extra fuel and water. Always share your route and expected finish time. Identify bail-out points and backup transport options.

Making the Most of UK Summer Evenings: Those magical hours between 6-9 PM offer some of the year’s best running conditions. Plan “sunset chaser” routes hitting western-facing viewpoints, coastal paths, and ridge walks. The extended light means you can explore remote terrain that feels too challenging for winter evening runs.

Logistics Tips:

  • Start around 6AM for full-day adventures
  • Use early morning public transport to access starting points
  • Plan photo stops, these become treasured annual memories
  • Build in scenic breaks without racing against darkness
  • Consider creating an annual solstice tradition route

[Get detailed route planning strategies and safety checklists in our complete guide here]

Recovery

Mental Reset: 67% of runners report lower stress levels after just 20 minutes of running - ideal for hectic workdays. Personally, I often find after a day at work or a morning, if I’m squeezing in a lunch run, that I feel much better after the run - it is often difficult to get motivated to get out the door though. The best approach is to arrange to run with someone - that accountability makes it more difficult to skip.

Second Interval

UK Summer Running - Mastering Variable Weather

UK summer weather’s unpredictability isn’t a bug, it’s a feature that creates resilient runners. Learning to thrive in changeable conditions makes you adaptable and race-ready regardless of what weather arrives on event day.

Reading Weather Changes: UK summer can deliver four seasons in one run. Key skills: recognising when light rain improves conditions vs. when heavy rain creates danger, adapting to 10-15 degree temperature swings during long runs, and understanding how cloud buildup and wind shifts signal incoming weather.

Smart Summer Layering:

  • Base layer: Moisture-wicking, never cotton, quick-drying
  • Middle layer: Removable/packable long-sleeve with ventilation options
  • Outer layer: Ultralight rain jacket that packs to energy-bar size
  • Carry system: Lightweight pack or belt for removed layers

Humidity Management: UK summer humidity can be surprisingly challenging. High humidity days require conservative pacing, extra hydration, and realistic expectations. Save hard efforts for clearer conditions, use muggy days for easy runs and technique work.

Perfect Weather Strategy: When UK conditions align beautifully (rare but magical), adjust your schedule to take advantage. Swap easy days for quality sessions, extend planned runs, or tackle your most challenging routes. These windows are precious, seize them.

Building Weather Resilience: Don’t become dependent on perfect conditions. Each weather challenge builds mental toughness for race day. Embrace variability as what makes UK running unique and rewarding.

[Find complete weather adaptation strategies and gear recommendations in our full article here]

Recovery

Longevity Boost: Runners of 50 have a 30% lower risk of heart disease compare to non-runners. Good news for me as I celebrated my 51st birthday earlier this year!

Final Interval

Summer Hydration - Calculate Your Needs

Even in the UK’s moderate climate, proper hydration significantly impacts performance. Understanding your individual needs through simple testing helps whether you’re running in 15°C drizzle or those rare 25°C scorchers.

Test Your Sweat Rate:

  1. Weigh yourself nude before running
  2. Track all fluids consumed during run
  3. Weigh immediately after (before drinking)
  4. Calculate: (Pre-weight - Post-weight + Fluid intake) ÷ Time = Sweat rate

UK Example: 68kg → 67.3kg, drank 500ml, ran 60 min = 1.2L/hour Even in typical UK conditions (15-20°C), many runners lose 0.8-1.5L/hour.

Electrolyte Needs: You lose about 400-700mg sodium per litre of sweat. For our example runner: 1.2L/hour × 500mg = 600mg sodium lost. Target replacing 50-80% during exercise (250-400mg/hour).

UK-Specific Hydration Strategy:

  • Under 60 min: Pre-hydration focus (400-500ml, 2-3 hours before)
  • 60-90 min: 150-200ml every 15-20 minutes, add electrolytes after hour 1
  • 90+ min: Target 80-90% sweat rate replacement, 200-300mg sodium/hour

Weather Adjustments:

  • Cool/wet: Reduce intake 10-20%
  • Humid (common): Increase 20-30%
  • Windy: Slight increase
  • Rare hot days: Increase 40-50%, emphasise electrolytes

Recovery: Replace 150% of losses over 4-6 hours with sodium-containing fluids.

[Access detailed electrolyte formulas and condition-specific strategies in our complete hydration guide - here]

Cool-Down

“I don’t run to add days to my life, I run to add life to my days” - Ronald Rook

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