Can exercise cause armpit lumps?

Yes, exercise can cause armpit lumps. Though not common, these lumps are usually caused by a condition known as hyperhidrosis or excessive sweating. Symptoms of hyperhidrosis include redness and swelling in the armpits and feeling tender or painful to the touch. Exercise can be a trigger for this condition so if you notice any small lumps developing in your armpits after exercising, it's best to seek medical advice immediately.

In some cases, having an active lifestyle may also increase your risk for underarm cysts or abscesses which are hard nodular masses filled with pus that may form in the armpit area due to sweat glands becoming blocked or infected from friction caused by exercise gear such as pads and gloves you wear while working out. These cysts don't always require treatment but they should still be assessed by a doctor if they become painful or persistently swollen.

To reduce your chances of developing either hyperhidrosis-induced lumps or cysts/abscesses in your armpits due to exercising, make sure that you always wear breathable clothes during workouts (especially bras!) and switch out any padding/protection gear regularly to keep bacteria out of the area. Finally, make sure that you shower right away after working up a sweat as this will help prevent any impurities from building up on skin surfaces where infection is more likely to occur!