Electrolyte Imbalance (Hypokalemia, Hypomagnesemia, Hyponatremia): This is a common cause of muscle cramping and twitching. The recent onset of cramping in new areas and the description of "electric zaps" in the arms could be indicative of an electrolyte imbalance, which can cause neuromuscular irritability.

Dehydration: Inadequate hydration can lead to electrolyte imbalances and muscle cramping. Given the recent increase in symptoms, dehydration could be a contributing factor.
Overuse or Muscle Strain: Repeated strain on muscles can lead to cramping and twitching, especially if the individual has recently increased physical activity.
Nutritional Deficiencies (e.g., Vitamin D, Calcium): Deficiencies in certain nutrients can affect muscle function and lead to cramping and twitching.
Medication Side Effects: Certain medications can cause muscle cramping and twitching as side effects.

Neurological Disorders (e.g., Amyotrophic Lateral Sclerosis (ALS), Peripheral Neuropathy): While less common, these conditions can present with muscle twitching and cramping. Early diagnosis is crucial for management and prognosis.
Thyroid Disorders (Hypothyroidism, Hyperthyroidism): Both underactive and overactive thyroid glands can cause muscle symptoms, including cramping and twitching.
Diabetic Neuropathy: In individuals with diabetes, neuropathy can cause a variety of symptoms including muscle cramping and twitching.

Channelopathies (e.g., Hypokalemic Periodic Paralysis): These are rare genetic disorders affecting ion channels in muscles, leading to episodes of muscle weakness and paralysis, sometimes preceded by cramping.
Toxin Exposure (e.g., Lead, Mercury): Exposure to certain toxins can cause a range of neurological symptoms, including muscle cramping and twitching.
Muscular Dystrophies: A group of genetic disorders characterized by progressive muscle weakness and degeneration, which can include symptoms of cramping and twitching in some cases.