<p>Alfie - </p>
<p>Although there is no sure general answer for your question, because each person’s singing technique has different strengths and weaknesses, your instinct is likely correct - all of the muscles surrounding your larynx are much less tense, so you aren’t “getting in your own way” when singing high notes. </p>
<p>As my training (and my boss
) mandate, I looked up your question to find any concrete physiology behind it, because I suspected increased blood flow to all the muscles after vigorous exercise might be helping you, too. Here’s what I found, from the website of a very respected voice center:</p>
<p>"A study by Elliott, Sundberg, & Gramming (1995) attempted to determine if vocal warm-ups prior to singing yielded the same effect as warming up other parts of the body, i.e., increasing blood flow to muscles thereby decreasing their thickness and increasing their pliability. Although the results of this study were inconclusive as to the exact effect of vocal warm-ups, several reasons still support the use of vocal warm-ups. Elliott, Sundberg, & Gramming emphasized that changing pitch undoubtedly stretches the muscles. They also noted that many singers subjectively indicated improved vocal functioning following warm-ups. </p>
<p>Warm-ups should not be confused with vocalises. Warm-ups, as in weight training, are used to stretch the muscles to prepare them for work without injury. Vocalises are tasks aimed at acquiring a particular skill, i.e., the actual exercise itself. For example, some schools of thought encourage simple, quiet glides across the range as an effective warm-up. On the other hand, using a staccato (short) “ha-ha-ha” on 1-3-5 of a scale is to encourage onset and flexibility. Many singers will use a variety of vowels, consonants, or arpeggios to “warm” the voice; however, these techniques may actually be encouraging articulatory precision or vowel balancing as in rapid “me-may-mah-mo-mu,” or balancing “registers” as in sung single vowels on 1-5-6-5-1, etc."</p>
<p><a href=“http://www.gbmc.org/voice/vocalwarmups.cfm[/url]”>http://www.gbmc.org/voice/vocalwarmups.cfm</a></p>
<p>Although the warm-up/vocalise distinction wasn’t part of your question, I thought it was great info for all singers! :)</p>