Bob Johnson, a 69-year-old male, retired several years ago. Due to recent financial struggles, however, he has been forced to work part-time as a greeter at a local store. He lives with his wife, who is hard of hearing, in a two-story townhouse. Over the past few years, Mr. Johnson has noticed his voice gradually becoming hoarse, soft and strained. Consequently, people have a hard time understanding him, requiring him to repeat himself frequently. He also says speaking requires great effort and that his voice fatigues easily. Recently, his supervisor commented that Mr. Johnson's voice might deter customers from shopping at the store if they are unable to understand him. Once considered the life of the party, Mr. Johnson now avoids socializing with his family and friends, especially in noisy environments. Additionally, he has stopped reading books to his grandchildren, a pastime he truly cherishes, and most importantly, Mr. Johnson worries that his wife will have trouble hearing him call to her if there is an emergency.

The effect of aging on a person's voice is a major challenge in the United States, as the aging population increases. According to the National Institute on Aging, by 2050, the number of people 65 years and older will more than double from 40 million to 89 million. Additionally, other research indicates that workforce participation among the elderly is also increasing, contrary to the declining trend of increasing rates of joblessness among younger adults. To continue to be employable, our aging population must be able to communicate effectively. Although surgical procedures exist, with mixed results, to improve age-related vocal deterioration, voice therapy provides a low-cost, non-invasive, and most importantly, effective treatment alternative for people with age-related voice changes. To date, two specific voice therapy approaches have demonstrated short-term efficacy in the treatment of age-related voice changes: vocal function exercises and phonation resistance training exercises.

The starting line: How does the voice age?

A well-known consequence of aging is muscle loss and change, also known as sarcopenia. Although the cause of sarcopenia is multi-dimensional, one prevailing contributor is physical inactivity. A similar age-related pattern of muscle loss and change appears true of the vocal folds, which leads to a condition known as presbyphonia. Like limb skeletal muscle, vocal inactivity remains a putative cause of vocal fold atrophy. Additionally, presbyphonia results from loss of respiratory strength, decreased thyroarytenoid activity, and stiffening of the vibratory portion of the vocal folds. The resulting old-sounding voice comes with changes in fundamental frequency-higher pitch in men and lower in women-decreases in vocal intensity, deterioration of voice quality, and complaints of effortful phonation. A 2011 article in Otolaryngology-Head Neck Surgery showed that such changes affect up to 30 percent of the population and negatively impact quality of life, limit social interaction, and lead to anxiety and depression, as it did for Mr. Johnson. 

What is the role of voice treatment? 

Although we cannot change some of the voice's natural physical decline, we can help it retain some key functionality by borrowing from research in exercise physiology and voice science. Research findings on older singers jibe with those on competitive older athletes: it's "use it or lose it." Research has shown that those older individuals who remain active maintain physical independence longer than those individuals with a sedentary lifestyle. Similarly, elderly singers have demonstrated a louder and clearer speaking voice than elderly non-singers. This finding suggests increased vocal activity may prevent vocal aging and help maintain vocal longevity.

In selecting voice treatment for presbyphonia, clinicians should address specific patient complaints: decreased loudness, increased roughness and breathiness, and increased phonatory effort. Accordingly, voice therapy goals for age-related dysphonia target increased vocal loudness, synergy of respiratory support and phonatory control, and improved vocal quality. Only two therapy techniques, both based in principles of exercise physiology, have been scrutinized through research: vocal function exercises (VFE) and phonation resistance training exercises (PhoRTE). Those two voice therapy programs have been found to improve age-related voice changes and lead to increases in voice-related quality of life and decreases in phonatory effort in age-related dysphonia. 

Vocal function exercises in action

VFE is a series of voice exercises that have been validated and described as "voice manipulations designed to strengthen and balance the laryngeal musculature and to balance airflow to muscular effort." In the original 1994 validation study, normal female participants reduced their rate of airflow, increased maximum phonation time, increased frequency range of phonation and noted high levels of overall satisfaction with the exercises that may improve overall adherence.

Vocal function exercises in the treatment of presbyphonia have demonstrated success in studies by several different authors. Gorman and colleagues studied VFEs in elderly men and found that after 12 weeks of training, the men demonstrated increased maximum phonation time and improved glottal closure. Sauder and colleagues studied the use of VFE's in presbyphonia and found a decrease in the severity of perceived dysphonia, improved self-ratings of dysphonia, and reduced vocal effort after therapy. Tay and colleagues compared treatment and no-treatment cohorts in a group of 65-year-old choir members. They used VFEs and found improvement in acoustic measures, increased maximum phonation time, and reduced vocal roughness. 

The vocal function exercises consist of the following four exercises that are to be completed

two times each, twice a day, seven days a week, with emphasis on a frontal focus to the sound.

1. Maximum sustained phonation on /ĩ/ on the pitch F above middle C (males dropped down an octave)
2. An ascending glide over the entire pitch range on /oɫ/
3. A descending glide over the entire pitch range on /oɫ/
4. Maximum sustained phonation on the pitches middle C and D, E, F, and G above middle C (males dropped down an octave) on /oɫ/

PhoRTE in action

The program, phonation resistance training exercises (PhoRTE, a homophone to the Italian word forte meaning loud and strong), seeks to reverse the sarcopenic changes of the vocal mechanism and restore the perception of a "youthful" sounding voice through loud voice production. Data indicate that loud voice production increases laryngeal muscle activity and leads to increases in subglottal pressure and improvements in vocal intensity and vocal quality in adults with presbyphonia. Further, speaking with a megaphone mouth shape-a wide mouth opening, spread lips, a narrow pharyngeal space, and a high laryngeal position-which occurs with the vowel /a/, maximizes phonatory efficiency and loudness and helps to recalibrate the amount of phonatory effort. Those changes allow a speaker to shout without straining the voice. 

The PhoRTE program consists of the following four exercises:

1. Sustain the vowel /a/ with a loud, energized voice for as long as possible.
2. Glide from low to high and from high to low on the vowel /a/ over the entire pitch range using a loud, energized voice.
3. Shout functional phrases using a loud and higher-pitched voice, like calling over a fence.
4. Using the same phrases from Step 3, produce a strong, authoritative voice at a low pitch level.

In line with resistance strength training principles from the American College of Sports, the clinician sets an initial exercise workload of the PhoRTE exercises at 50 to 60 percent of the total vocal intensity range or 5 dB above the average vocal intensity, whichever is greater. The voice clinician reevaluates the exercise workload weekly and increases the minimum workload as muscular force and endurance improve. To that end, the voice clinician progressively increases the vocal intensity target by 5 dB increments weekly until the patient reaches the final target of +20 dB SPL above the average vocal intensity (ideally, 80-90 dB SPL). The patient performs repetitions of loud and strong voice (about eight to 10 repetitions) to the point of muscular fatigue using various speech stimuli. During voice treatment sessions, the patient completes two sets of the PhoRTE exercises and between each set observes a one-minute rest period. Patients complete the PhoRTE program twice daily. By the end of voice treatment, the patient should be able to achieve a vocal intensity between 80 and 90 dB, as measured by a sound level meter positioned at a microphone-to-mouth distance of 30 cm. Once discharged from voice treatment, the patient continues to perform the third and fourth PhoRTE exercises, three times per week, but no more than once per day, at their target vocal intensity to maintain their vocal status. 

Preliminary data indicate that the use of PhoRTE for the treatment of presbyphonia demonstrates improved vocal outcomes and improved voice-related quality of life. In a randomized, controlled trial comparing VFE, PhoRTE, and a no-treatment control group, participants in both the VFE and PhoRTE groups demonstrated vocal improvement, while the control group remained stable or demonstrated a slight decline in vocal effort. However, the PhoRTE group demonstrated an increased reduction in vocal effort and increased treatment satisfaction with the process and the outcome of therapy.   

Finally, an important point needs to be made: Loud voice in this patient population is not a risk factor for phonotrauma. Although the PhoRTE voice therapy program aims to decrease the phonatory glottal gap, the vocal folds approximate one another but not past the point of a barely adducted/abducted vocal fold configuration. This configuration maximizes vocal economy by minimizing impact stress and thus, the risk of phonotrauma, while at the same time increasing vocal loudness. This point however, underscores the need for collaborative work with the otolaryngologist to ensure that presbylaryngeus is indeed the origin of the dysphonia and that that glottal configuration is optimal for the use of exercises requiring loud voice use. 

The finish line:

Many people diagnosed with presbyphonia are unaware that voice treatment is available and believe it to be an unavoidable consequence of aging. However, patients who undergo voice treatment for presbyphonia report satisfaction with their vocal capabilities and improved functional voice status. Although the impact of vocal inactivity on age-related voice changes still warrants investigation, voice treatment programs such as vocal function exercises and PhoRTE show promise in successfully rehabilitating the aging voice.

Remember our client, Mr. Johnson? Well, frustrated by his voice, he decided to seek an evaluation by an otolaryngologist. After undergoing a videostroboscopic examination to look at his larynx, Mr. Johnson learned that he had age-related changes to the vocal folds. The otolaryngologist recommended that Mr. Johnson receive voice therapy from a speech-language pathologist to address his problem. After completing four weeks of voice therapy, Mr. Johnson felt confident about his voice. He returned to spending time with his grandchildren and was recently promoted senior greeter.