How sleep and training load can affect SpO2

Athletes are very in tune with their bodies. Sometimes an athlete doesn’t wake up feeling right. Sometimes sleep is just not right. It is common to check heart rate and not much more. Have you ever thought about checking your blood oxygen (SpO2) with a pulse oximeter?


Case Report: The athlete woke up feeling just “not right” and he observed that his morning SpO2 was low on Tuesday after a big training block as seen with the Training Stress Score (TSS). The sleep hours were about 7 and 6 during this training block. The resulting SpO2 following the training block was 93%. This is a great case where the athlete may feel alright to go train and continue the hard exercises, but the fact of “not feeling right,” low sleep hours, and low SpO2 suggested that the athlete should either take the day off or train very light and concentrate on proper sleep. The athlete achieved 9 hours of quality sleep for 2 consecutive days and the SpO2 normalized and the following training days went very well.  This is a great example of how data is the “second voice” of the athlete and paying attention to the numbers can result in a good training block and even avoid an over-training scenario.


Johnathan Edwards is a medical doctor with 30 years of sport medicine experience. A former professional athlete in the sport of motocross and a Category 1 bicycle racer, Johnathan understands human performance. He obtained a complete Physiology degree from UC Davis, medical school in Norfolk, VA, Internal medicine in Las Vegas, Sports medicine in Utah, and Anesthesiology in Florida. Today he is a performance coach, clinical instructor, team doctor for many cycling teams, UFC, motocross and Olympic athletes. Husband and father, he aspires to live part time in France and the United States, and riding his bike. Full Disclosure – Johnathan is a consultant for Masimo and the Mighty Sat.