Does starving mean being weak? Not at all! — a case report

Abstract

Fasting is gaining the general popularity. Athletes also often fast to lose weight or due to cultural premises.
The consequences of severe fasting on strength and sports performance are not well understood.
Therefore, this paper presents a case of a 32-year-old male athlete who underwent a 7-day strict water fast
merged with strenuous strength training. He applied Continuous Glucose Monitoring during the fast and
the 7 days of a normal isocaloric diet. An athlete recorded training and measured the muscle’s peak force.
His fat mass decreased from 13.8 kg to 13.2 kg and his fat-free mass decreased from 63.9 kg to 61.2 kg.
The lowest blood glucose of 58 mg/dL was noted at the end of 7th day. The athlete observed numerous
smaller dips during the day and meaningful glucose spikes during workouts. The hypoglycaemia was
clinically asymptomatic, and the athlete efficiently performed everyday activities. His training performance
and peak force measurements increase slightly. Severe fasting did not provide any harmful symptoms.
Body homeostasis was quickly rebuilt. Prolonged fasting does not necessarily limit exercise performance
among strength athletes. Athletes could even make strength progress during periods of fasting.