Athletic testing has become a vital part of the sports community. Monitoring an athlete’s performance allows individuals and coaches to assess how the body is handling training and competition. When it comes to deciding which tools and models to utilize for monitoring training load – individuals are faced with a multitude of options. But which one is the best?

A sport-science conference, “Monitoring Athlete Training Loads The Hows and the Whys“, was held in 2016 where experts came together to discuss and share research on modes of athlete training (4). A group of researchers gathered the key findings discussed to provide a scientific, consensus review on athlete-load monitoring and the tools used for assessment.

Let’s Take A Look At What The Science Found

Training load can be divided into internal and external load categories. Internal load is defined by psychological and physiological stressors. Measures include heart rate, ratings of perceived exertion (RPE), and oxygen consumption.  External loads are objective measures of an athlete’s work. Measures commonly include power output, speed, and time. The table below (Table 1) summarizes internal and external measures used when evaluating training load. The following tools and models generate and/or use these measures to assess an athlete’s training load, performance ability and/or injury risk. (4)

Training Load

GPS Measures

Global positioning system (GPS) parameters are a common external load measure for team sports (4). GPS devices help to measure distance, velocity, and acceleration (1, 26, 27). They can also acquire external-load metrics such as, the number of efforts an athlete undertakes in variant speed or acceleration thresholds (2, 4, 24). An acceleration effort ⏤ typically occurring within the first few steps is measured as the time an athlete spends above a given acceleration rate (i.e., 3 m/s²) (4). While research has suggested use of GPS devices as a valid and reliable tool for quantifying distance and velocity (25), there are caveats. Research suggests GPS accuracy is improved with higher sampling frequency (15, 27). Meaning, individuals should perform several trials when using GPS devices to obtain accurate measures. To add, if the trail or intervention being assessed includes an athlete having a high rate of change in velocity, the GPS becomes less accurate in measuring velocity (1, 27).

Tools For Strength And Power Training

Training programs most commonly include strength and power training (4). Resistance exercise is typically included in such training programs. Strength and power training loads are monitored using volume load and mechanical work performed during resistance exercise (20). Mechanical work is determined by the product of force and displacement during exercise. Research has suggested various tools and methods to measure such an intervention, including: inertial sensors and accelerometer (11, 12), linear position transducers (8), video analysis (9, 10), force plates (5), and V-scope (13). Linear encoders, inertial sensors and accelerometers demonstrate greater promise in evaluating training load in the gym compared to the other tools mentioned previously. Video analysis, force plates, and V-scope tools can be more costly and have proven to be difficult to implement in real-life settings (4).

Tools And Strategies for Youth Athletes

It is important to appropriately monitor and manage training loads in youth athletes. Research has found high volumes of training lead to early retirements and greater risk of injury (14). For example, a 2005 study found youth cricket fast bowlers who had less than 3.5 days rest between bowling interventions experienced 3.1 times greater injury risk (6). A 2002 study found youth baseball pitchers who totaled more than 600 pitches (high volume) in a season experienced the greatest risk of injury compared to players of moderate and low pitch volume (19).

Researchers suggest youth athletes maintain a training diary (4). A training diary allows youth athletes to understand their personal training load, as well as the significance and ramifications of their own attendance, performance and health (4). Lifestyle factors should be taken into account, as studies have determined a relationship between non-training and non-competition stressors to burnout and/or abandoning sport (4). Studies also suggest RPE-measures should be used with caution when monitoring youth athlete training loads (4, 23, 28). RPE-measures are scored by personal evaluation, and youth athletes tend to be unreliable in regard to self-assessment (4). Multiple internal load metrics are suggested to be used to evaluate youth training loads (4).

Psychological Measures

Psychological stressors can have a significant impact on an athlete’s performance. Studies have suggested different demographics (e.g., age, gender, ethnicity) and an individual’s psyche impact the degree of vulnerability an athlete experiences (4, 22). An athlete’s degree of vulnerability can dramatically impact recovery potential, exercise capacity, – stressors, and stress tolerance (4). Research focused on overtraining has demonstrated psychological stressors are more sensitive and consistent compared to physiological stressors (22).

Psychological measures can be assessed using the Profile of Mood States (21), Borg RPE (3), session RPE (sRPE) (7), and the Recovery-Stress Questionnaire for Athletes (16, 17). Research has verified the mentioned assessment for validity and accuracy and are commonly used to monitor athletes. The Acute Recovery and Stress Scale has also been determined as a valid assessment to quantify recovery and stress, but has become so recently (18).

So, Which Measure? Which Tool?

To sum up, the type of intervention, team or individual sport, finances, and the environment should all be considered when determining what tools and/or measures should be used for monitoring training loads (4). Stay tuned for Part 2, where we will continue to review the pros and cons of models and tools used in monitoring athlete training load.


Thank you for reading! I hope you feel more informed. If you have any questions or comments, please feel free to leave a shout out!






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