Understanding Muscle Cramps: Causes, Fatigue, and the Role of Physiotherapy by Bill Kelly APA Physiotherapist
Muscle cramps are sudden, involuntary, and often painful contractions that occur in skeletal muscles. They’re a common complaint among athletes, gym-goers, and even sedentary individuals after prolonged inactivity. While cramps are usually short-lived, they can significantly affect performance, recovery, and confidence -especially when they strike during a critical moment in competition.
Why Do Muscle Cramps Happen?
Although traditionally blamed on dehydration or electrolyte loss, more recent evidence suggests that neuromuscular fatigue plays a major role in cramp development. When a muscle becomes fatigued, the communication between motor neurons and muscle fibres can become unbalanced. This leads to increased excitatory activity and reduced inhibitory feedback within the spinal cord, resulting in the muscle contracting involuntarily and not relaxing properly (Miller et al., 2010).
Other key contributing factors include:
Dehydration and electrolyte imbalance: Excessive sweating can reduce sodium, potassium, and magnesium levels, influencing nerve and muscle function.
Neuromuscular fatigue: High workloads, especially during end stages of games or training, alter the firing threshold of alpha motor neurons.
Poor conditioning: Inadequate pre-season preparation or muscle weakness can predispose athletes to cramping.
Restricted tissue or neural mobility: Tight fascial or neural structures can increase susceptibility during repetitive or high-intensity activities.
Environmental stress: Exercising in hot, humid conditions accelerates fatigue and electrolyte loss, compounding cramp risk.
In many cases, a combination of fatigue, inadequate recovery, and altered neural control are the real culprits - not just fluid loss.
The Role of Physiotherapy
Physiotherapy plays a crucial role in both managing and preventing muscle cramps. A comprehensive assessment can help identify whether cramps are due to mechanical overload, fatigue, or neural irritation.
A physiotherapist may use several evidence-based strategies, including:
Movement and strength testing to assess for imbalances or poor activation patterns that predispose certain muscles to fatigue.
Manual therapy and soft tissue techniques to release tight muscles and improve blood flow.
Neural mobilisation for nerves that may be restricted or hypersensitive.
Progressive strengthening and conditioning programs to improve muscular endurance and resilience.
Education on hydration, recovery, and load management, tailored to the demands of the sport or activity.
Addressing these factors helps restore normal neuromuscular control and reduces the likelihood of recurring cramps. Physiotherapists also play an important role in return-to-play planning, ensuring athletes rebuild endurance gradually and maintain adequate recovery practices between sessions.
Can Pickle Juice Help?
One of the more intriguing and widely discussed remedies for muscle cramps is pickle juice. Despite its popularity, its mechanism of action is not linked to hydration or electrolyte replacement - it simply works too fast for that. Instead, research indicates that pickle juice activates oropharyngeal reflexes that act on the nervous system.
The strong, acidic flavour of pickle juice (high in acetic acid) stimulates sensory receptors in the mouth and throat, which send inhibitory signals to the alpha motor neurons responsible for the cramping muscle (Craighead & Kenney, 2017). This neural reflex interrupts the misfiring and allows the muscle to relax.
Studies have demonstrated that consuming 1–2 mL/kg of pickle juice can reduce cramp duration by about 37% compared to water or no treatment (Miller et al., 2010). Other research supports similar findings, suggesting the effect occurs within 30–90 seconds, long before electrolyte absorption would be possible (Miller et al., 2014).
While more research is needed, pickle juice appears to be a safe, rapid, and effective in-game option for athletes, provided it is used alongside comprehensive hydration and recovery strategies.
Key Takeaways
Muscle cramps are primarily a neuromuscular problem, often driven by fatigue and reduced inhibitory control rather than dehydration alone.
Physiotherapists play a key role in identifying mechanical and neural causes, improving endurance, and preventing recurrence.
Pickle juice may provide rapid symptom relief through neurological reflexes, not electrolyte replacement — making it an interesting, research-backed tool for athletes during games.
Long-term prevention relies on conditioning, recovery, and load management, all central components of physiotherapy care.
References
Craighead, D. H., & Kenney, W. L. (2017). Proposed mechanisms by which pickle juice suppresses electrically induced muscle cramps: a review. Journal of Athletic Training, 52(7), 709–714.
Miller, K. C., Mack, G. W., Knight, K. L., & Hopkins, J. T. (2010). Reflex inhibition of electrically induced muscle cramps in hypohydrated humans by pickle juice. Medicine & Science in Sports & Exercise, 42(5), 953–961.
Miller, K. C., & Stone, M. S. (2014). Exercise‐associated muscle cramps: causes, treatment, and prevention. Current Sports Medicine Reports, 13(4), 197–200.
Schwellnus, M. P., Drew, N., & Collins, M. (2018). Muscle cramping in athletes – risk factors, clinical assessment, and management. Clinics in Sports Medicine, 37(2), 261–273.
Minetto, M. A., Holobar, A., Botter, A., Farina, D. (2013). Origin and development of muscle cramps. Exercise and Sport Sciences Reviews, 41(1), 3–10.