the state of being stretched tight.
“the parachute keeps the cable under tension as it drops”
synonyms: tightness, tautness, rigidity
What does fly casting and rhythmic (ribbon) gymnastics have in common? Tension. Both sports require a masterful a skill of maintaining tension on the line.
Because of this I believe Ribbon gymnasts would make great fly casters. If had to pick the number one fundamental for fly casting it would be maintaining tension on the line. You can get away with a sloppy stop or too long/short of a casting stroke. But if you do not maintain the tension you cannot throw the line. It just won’t go. You are throwing nothing.
Practice maintaining fly line tension: