The Relationship Between External And Internal Training Load Indicators In Collegiate Women Soccer Players

INTRODUCTION The process of quantifying training stress—commonly referred to as training load—during practices and competitions is vital in assessing whether an athlete is adapting positively to a training program. External training load refers to objective measures of the work performed by the athlete, while internal training load can be described as the relative biological load imposed on the athlete during training and competition. PURPOSE To examine the relationship between a commonly utilized measure of internal training load, sRPE, and a variety of external training load indicators representing both the volume and intensity of the work performed by collegiate women soccer players. METHODS This was a prospective observational study with data collected during the summer and fall of 2021. The participants were 23 collegiate women soccer players (age 20 ± 2.3 years, height 171 ± 4.8 cm, 59 ± 6.2 kg) of a division II state university. Descriptive statistics for all training load indicators were generated, while the association between variables was assessed using Pearson correlation coefficients. Magnitude of correlation coefficients were interpreted as trivial (<0.1), small (0.1 – 0.3), moderate (0.3 – 0.5), large (0.5 – 0.7), very large (0.7 – 0.9), and nearly perfect (>0.9). RESULTS There were moderate and large correlations between sRPE and two different external training load indicators representing the volume of the work performed. sRPE was largely correlated with player load (r = 0.64, p < 0.01) and moderately correlated with the number of sprints (r = 0.41, p < 0.01). Meanwhile, there were only trivial and small correlations between the external training load indicators representing the intensity of the work performed with the highest correlation being with the metabolic power score measured relative to the athlete's body weight (W/kg; r = 0.23, p < 0.01). CONCLUSION The main finding from this analysis was the large correlation between a commonly used measure of internal training load and a measure of global external training load representing the volume of work performed by the athlete during training and competition. This finding supports the use of sRPE as a global measure of internal training load, which may serve as a cost efficient manner to monitor athletes.