The Effect of L-Tryptophan Intake on Dynamic Strength in Paralympic Powerlifting

Area of Science:

• Sports Science
• Nutritional Supplementation
• Human Performance

Background:

• L-tryptophan's effects on endurance athletes are debated.
• Its impact on maximal strength sports, particularly powerlifting, is under-researched.
• Investigating L-tryptophan for Paralympic powerlifters addresses a gap in sports science literature.

Purpose of the Study:

• To determine if L-tryptophan supplementation enhances dynamic strength indicators in Paralympic powerlifting athletes.
• To explore the time-course and load-dependency of L-tryptophan's effects on strength performance.
• To provide evidence-based insights into nutritional strategies for para-athletes.

Main Methods:

• Randomized, double-blind, crossover trial with 13 Paralympic powerlifters.
• Supplementation with L-tryptophan or placebo for 72 hours prior to training sessions.
• Objective strength assessment using an encoder to measure mean propulsive velocity (MPV), maximal velocity (Vmax), and power (PO) at various loads (45% and 80% 1RM) and time points (pre, post, 24h, 48h).

Main Results:

• L-tryptophan supplementation led to significantly higher pre-exercise MPV, Vmax, and PO compared to placebo.
• These performance enhancements were transient, diminishing after exercise.
• No sustained benefits of L-tryptophan supplementation were observed at 24 or 48 hours post-supplementation.

Conclusions:

• L-tryptophan supplementation may provide a short-term improvement in pre-exercise strength performance in Paralympic powerlifters.
• The mechanism might involve enhanced neuromuscular relaxation.
• Further research is needed to understand the long-term efficacy and optimal use of L-tryptophan in strength sports.