fluctuating/changing/variable training load, i.e. different training load intensities

Training load – the cumulative amount of stress placed on an individual from a single or multiple training sessions over a period of time.
https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web... (p. 1)

Postupnost i valovitost dinamike opterećenja (training load) uslovljena je …
http://www.usms.rs/kontent/stranicy/sport_info_centar_pzz_pr... (str. 56)


…coaches strategically fluctuate Training Load and recovery to push the limits of adaptation and avoid overtraining…
https://blog.rypt.app/sandc/the-importance-of-training-load-...