Just like changing our timing to control our speed (or rate of speech), we also need to work on our degree of body tension when we want to sound more fluid and less tense.
One of the reasons non-native speakers speak with excess tension is they try very hard to say words (and make sounds) correctly, but they frequently don’t monitor how much effort they are using, so they may not be aware that they are using more tension than needed to make a sound.
All this excess tension often goes into the back, shoulders, neck, and other vulnerable areas, creating pain and discomfort, and also making our speech overly controlled, less fluid or free flowing, and tense-sounding.
Since most people want to sound natural, confident, and comfortable when they speak, all this tension is a deterrent. It can get in the way of effective speech. There’s no reason not to minimize this tension, but most people aren’t even aware they have it, much less that it affects their delivery. Instead, people try “harder” to speak “better,” often creating even more tension.
Awareness & Change:
Knowing your tension is affecting your speech is the first step, and then each of us needs to learn how to maximize our focus and attention to key/challenging sounds without creating additional (unnecessary) tension.
Awareness really is the key here because once you can feel tension and monitor it, you can change it. Learning to release excess tension where you don’t need it and place it where you do (such as in the spine and tongue) helps non-native speakers begin to “let go” into the sounds and be more native-like in their delivery.