Fartlek (aerobic power).

The idea

Fartlek, Swedish for speed play, develops aerobic power by mixing continuous running with varied pace and terrain. The performer runs for a set time, changing speed and gradient spontaneously, for example jogging, then striding, then sprinting uphill, then recovering, without formal rest periods. Because intensity fluctuates, heart rate rises and falls around the aerobic zone, so the method trains both aerobic power and some anaerobic capacity. It is flexible, needs no equipment and can be done on roads, trails or hills. Progression comes from longer sessions, more or harder efforts, or tougher terrain. It suits games players and endurance athletes needing varied, sport-relevant conditioning, though the lack of precise control makes exact overload harder to monitor.

What earns the marks

• Fartlek means speed play and combines continuous running with spontaneous changes of pace and terrain.
• The performer varies speed and gradient, for example jogging, striding, sprinting uphill and recovering, without formal rest intervals.
• Fluctuating intensity raises and lowers heart rate around the aerobic zone, developing aerobic power and some anaerobic capacity.
• Progression is achieved through longer sessions, more or harder efforts, or more demanding terrain.

Common mistakes and how to put them right

• Thinking fartlek has fixed work and rest intervals.

  Put it right: Pace changes are spontaneous and continuous.

• Believing fartlek only develops anaerobic capacity.

  Put it right: It mainly develops aerobic power with some anaerobic benefit.

• Assuming it needs a track or equipment.

  Put it right: It can be done on varied natural terrain.

• Treating it as identical to continuous training.

  Put it right: Intensity fluctuates rather than staying constant.

Exam tips

• Define fartlek as speed play and give a concrete example of changing pace and gradient.
• Explain how fluctuating intensity develops aerobic power and some anaerobic capacity.
• Compare fartlek with continuous training, noting flexibility versus precise control of overload.