Methods of Monitoring Internal and External Loads and Their Relationships with Physical Qualities, Injury, or Illness in Adolescent Athletes: A Systematic Review and Best-Evidence Synthesis

Abstract

Background With the increasing professionalisation of youth sports, training load monitoring is increasingly common in adolescent athletes. However, the research examining the relationship between training load and changes in physical qualities, injury, or illness in adolescent athletes is yet to be synthesised in a systematic review. Objective The aim of this review was to systematically examine the research assessing internal and external methods of monitoring training load and physical qualities, injury, or illness in adolescent athletes. Methods Systematic searches of SPORTDiscus, Web of Science, CINAHL and SCOPUS were undertaken from the earliest possible records to March 2022. Search terms included synonyms relevant to adolescents, athletes, physical qualities, injury, or illness. To be eligible for inclusion, articles were required to (1) be original research articles; (2) be published in a peer-reviewed journal; (3) include participants aged between 10 and 19 years and participating in competitive sport; (4) report a statistical relationship between a measure of internal and/or external load and physical qualities, injury or illness. Articles were screened and assessed for methodological quality. A best-evidence synthesis was conducted to identify trends in the relationships reported. Results The electronic search yielded 4125 articles. Following screening and a review of references, 59 articles were included. The most commonly reported load monitoring tools were session ratings of perceived exertion (n = 29) and training duration (n = 22). Results of the best-evidence synthesis identified moderate evidence of positive relationships between resistance training volume load and improvement in strength, and between throw count and injury. However, evidence for other relationships between training load and change in physical qualities, injury, or illness were limited or inconsistent. Conclusions Practitioners should consider monitoring resistance training volume load for strength training. Additionally, where appropriate, monitoring throw counts may be useful in identifying injury risk. However, given the lack of clear relationships between singular measures of training load with physical qualities, injury, or illness, researchers should consider multivariate methods of analysing training load, as well as factors that may mediate the load–response relationship, such as maturation.

Pain Education in the Wellness, Training Performance, and Pain Intensity of Youth Athletes: An Experimental Study

“…Additionally, our results showed that higher levels of wellness were positively correlated with pain intensity, training hours, and number of competitions. This is in line with a study by Dudley et al from 2023 [42], which suggested that a high training volume might be associated with the health of athletes, increasing the risk of injury and illness.…”

The development of physical characteristics in adolescent team sport athletes: A systematic review

“…These contrasting results suggest that factors beyond training volume, such as content, intensity, specificity, and quality [ 68 ] may play a more significant role in influencing the outcomes than training volume per se. In a recent systematic review conducted by Dudley et al [ 69 ], the relationship between training load and physical qualities in adolescent athletes was examined. The review revealed moderate evidence supporting a relationship between resistance training volume load and strength.…”