The evidence for stretching exercises in the prevention of leg cramps is based mainly on expert opinion, an observational study, and one randomized controlled trial (RCT). The trial evidence suggests no benefit over non-stretch exercises. However, experts argue for stretching exercises based on a plausible mechanism of action and safety. Moreover, the placebo effect in leg cramp trials appears to be considerable, and exercises will encourage health promotion.

• Based on the observation that cramps appear to occur more frequently in contracted muscles, stretching a cramping muscle and activating the antagonist muscles is thought to help terminate a cramp and possibly reduce further cramps [Miller and Layzer, 2005].
• In an observational study (n = 44), people with frequent cramps were instructed to carry out simple stretching exercises three times a day until their cramps disappeared. The characteristics of the people who were investigated were not reported, including whether they were taking quinine. All reported cure within a week (21 people reported cure within 72 hours) and most remained cramp-free for follow-up periods as long as 1 year [Daniell, 1979].
• An RCT (n = 191) investigated stretching exercise in people (over 60 years of age) taking quinine. People were randomized to one of four groups defined by two 'advice' factors: undertake stretching exercises (versus non-stretch exercise) and stop quinine (versus placebo) [Coppin et al, 2005]:
• At 12 weeks, there was no difference seen in the number or severity of leg cramps and symptom burden in the exercise group compared with the non-stretch exercise group. An important consideration is that non-stretch exercises may have had a beneficial affect, making stretching exercises appear ineffective.
• Interestingly, one in four people who were advised to stop quinine had continued not to take quinine without any undue symptom burden, suggesting it may be possible in practice to stop quinine (in people on long-term treatment) without any recurrence of symptoms.