Running

Move · Cardio · Movement, Typed Supps

Steady effort that trains your heart like any other muscle.

Stage by stage

Warm-up (Blood flow increases): A gradual warm-up increases heart rate and blood flow to leg muscles, reducing injury risk and improving performance once you start.
During (Oxygen delivery ramps up): Heart rate and breathing rise to deliver more oxygen to working muscles, which burn a mix of fat and carbohydrate depending on intensity.
Immediately after (Mild fibre stress): Heart rate gradually returns toward resting levels; harder or longer runs cause mild inflammation in stressed muscle fibres.
Days later (Cardiovascular adaptation): The heart’s stroke volume and the muscles’ capacity to use oxygen both improve gradually with repeated aerobic training over weeks.

Muscles trained

Primary: calves, glutes, quads
Secondary: abs, hamstrings, hip abductors, hip flexors, shins

Intensity

9.8 METs (Running, 6 mph (10 min/mile)).

Time to effect

Weeks: Resting heart rate and other fitness markers begin improving.
Months: Larger aerobic capacity gains become measurable.

Related supplements

Common myth

“Running is bad for your knees.” In reality: Most research finds recreational running isn’t associated with higher rates of knee osteoarthritis in otherwise healthy people, and may even be protective by strengthening supporting muscle and cartilage.