According to Livestrong website, “The muscles of your core–the rectus abdominus, obliques, erector spinea and transverse abdominus–all work together to keep your spine aligned as you run. Running gives your core muscles an effective workout through the consistent spinal rotation that occurs when your arms and legs come forward with each stride. Running on terrain and uneven surfaces also challenges your core as you work maintain your balance and stability.”
I have been having stitches quite often when I run nowadays. I think it is because I have not been running regularly. As such, my body is not used to it when I try to run fast. Another reason I think is perhaps due to lifting weights. I have been doing a lot of lifting which requires core stability. As such, my core muscles might have already been in fatigue when I start my runs. Hence, this increases the chances of me experiencing stitches.
I managed to complete 5km today. Not in my best timing, but I am picking it back up slowly.