Abdominal muscle training: Plank
The plank and all its variations are considered one of the top 5 exercises for training the mid-torso, especially the abdominal muscles, without overloading the spine, as often happens with classic sit-ups (especially when performed with incorrect technique).
The difficulty of this exercise lies not so much in the movement itself, but in holding the plank position for a specific duration while consciously engaging the core muscles (abdominals, obliques, and lower back). This exercise is a must for anyone who wants to build their core strength while minimizing strain on their back.
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