One of the great things about martial arts is the ability to vary the training.

Forms/kata can be:
Large, middle or small frame
Soft, natural, or focused energy, healing or discharging
Focus on posture, breathing or balance
Fast, normal or slow speed
Work on snake, tiger, crane, leopard or dragon styles
Work on ‘pulling’ inwards (strangling, choking, throwing applications)
With the same techniques work on ‘pushing’ outwards (striking, pushing applications)
Focus on different body parts (feet, legs, hips, waist, upper torso, arms, hands, head)
Change intent, focus on body, skill level, opponent, power and venom
Work on mobility, rooting or ‘pulsing’ to create movement.

Other forms of solo exercise training can be very limited but martial arts have this great adaptability.