About THRESHOLD Book — FAQ
What is THRESHOLD about?
THRESHOLD is a 540-page book on the science of human endurance. It covers fatigue, lactate, VO₂ max, evolution, training science, and sport nutrition.
Who wrote it?
Hüseyin Akbulut — MSc Sport Sciences, Marmara University. Independent researcher and founder of sporeus.com.
When does it launch?
April 15, 2026. Join the waitlist at sporeus.com/en/threshold
Is there a free preview?
Yes. First 3 chapters free at sporeus.com/en/free-chapters
Is it available in English?
The Turkish edition (EŞİK) launches first. English edition (THRESHOLD) is in preparation.
Is it suitable for coaches?
Yes. With 275 scientific references, it provides an evidence-based foundation for coaching. Academic package: sporeus.com/en/academic
How many chapters?
22 chapters, 17 athlete profiles (Kipchoge, Dauwalter, Jornet), 275 scientific references.
Where can I buy it?
Pre-order info at sporeus.com/en/threshold. Purchase links available at launch.