Blood pressure —Exercise causes modest reductions in blood pressure in those who have borderline or moderate levels of high blood pressure. The average reduction in systolic and diastolic blood pressure for those who have high blood pressure and perform regular aerobic activity is 7 and 6 mmHg respectively.
One study (Using pedometers to increase physical activity and improve health: a systematic review. (https://www.ncbi.nlm.nih.gov/pubmed/18029834/) showed that simply increasing your step count can lead to a reduction in systolic blood pressure of ~4 mmHg. This may seem small, but a 5 mmHg drop reduces the chance of death by stroke by 14%! Individuals with blood pressure in a ‘normal’ range experience little long-term change in their BP at rest or with exercise.
Muscle fitness—Within three to six months, you could notice a 25% to 100% improvement in your muscular fitness by following a regular resistance program. Most of the early gains in strength are the result of the neuromuscular connections learning how to produce movement. Sometimes accounting for up to 50% of strength improvements in the early stages of a strength-based program.
Changes in muscle size from resistance training are highly variable, but can be as much as up to roughly 60% increases with a long-term resistance program.