Yoga helps to build core strength. A stronger core is a good foundation for improved posture and a stronger back.

Here's a 4 minute yoga core routine for the abdominal muscles from Sonia Ribas

https://www.youtube.com/watch?v=tXhxq_cYDRw

Here's a 5 minute yoga core sequence with Nadia Narain

https://www.youtube.com/watch?v=tXhxq_cYDRw

Here's a 10 minute (more challenging - slow down the video!) yoga core routine from Tara Stiles

https://www.youtube.com/watch?v=edNfbfelDHE

Tone your pelvic floor and improve your meditation by practicing mula bandha (the root lock): https://yogainternational.com/article/view/a-beginners-guide-to-mula-bandha-root-lock

NOTES: Please begin your yoga practice with the guidance of a qualified yoga teacher. Remember to exercise within your limits. Never force or strain. If you feel dizzy, light headed, faint or if you experience any other discomforts, stop exercising d and seek medical advice. Before any workout you should stretch to warm up and cool down afterwards. No heavy meals for two hours before workout. Keep hydrated by drinking water before and after yoga practice. Exercise in a light area, with enough free space around you. Wear comfortable clothing so you can move freely. If you are unsure about any medical issues please consult your doctor particularly if you are pregnant, nursing, taking medications, or have any existing medical conditions.