This news release describes a small study (~50 subjects) from UT Southwestern Medical Center showing that fairly aggressive and regular exercise in sedentary, middle-aged individuals can marginally increase maximum oxygen uptake and moderately improve the elasticity of the main pumping chamber of the heart (left ventricle).
Although the news release does a good job outlining the prescribed exercise regime, it makes unwarranted and confusing claims about reversing damage from “heart aging,” and suggesting the findings might “help prevent risk of future heart failure.”
This language is not justified. The research can’t tell us if risk for heart failure has been reduced in these study participants. Nor does it establish what is meant by “heart aging” and how that has been “reversed” by the intervention. The news release would have been markedly improved if such terms had been dropped, and focused more on what is — and is not known — about poor fitness as a risk factor for heart failure.
Cardiovascular health is a major health issue for middle-aged people and their health care providers. It makes research like this very interesting for readers, and we believe that places a premium on clear language.
This study had little to do with “heart aging” or even heart failure. So using such language in both the news release title, as well as the opening paragraph, sets up readers to be misguided and misinformed.
The intervention proposed is at least a half-hour of exercise 4-5 times per week. With the exception of a recommended 1 or 2 sessions involving weights or exercise machines (which would involve some cost) this intervention would require minimal financial investment. We’ll rate this Not Applicable.
The headline of the news release claims ‘Proper exercise can reverse damage from heart aging,’ but the study documents two outcomes: an ‘18% improvement’ in maximal oxygen uptake, and a ‘25% improvement’ in the elasticity of the left ventricle (the chamber primarily responsible for pumping oxygenated blood throughout the body).
“Reversal” implies a return to a previous state of function, but this study merely documents improvement in two cardiovascular outcomes that are commonly seen with regular aerobic exercise. It’s not clear if this change does in fact represent a “reversal.”
In addition, “damage from heart aging” is a confusing phrase. Poor oxygen uptake and a loss of heart elasticity are as much a consequence of sedentary lifestyle as they are a result of an aging heart. This is why a headline implying that exercise actually reverses aging in the heart is misleading.
Finally, the first paragraph of the release claims that exercise can help prevent the risk of future heart failure, even though the study itself makes it clear this outcome is speculative. At the very least, the release should have cautioned that a much larger and longer study would be needed to document any impact on heart failure outcomes.
The news release does an excellent job of outlining the exercise regime employed in the study. However, it does not mention that the study specifically recruited subjects between the ages of 45 – 64 who were sedentary. Given that one of the exercise sessions recommended in the study focuses on high-intensity interval training (HIIT) — and such training does come with potential risks for deconditioned individuals — it might have been advisable to mention that supervision for HIIT training should be strongly considered.
There are three noteworthy limitations to this small, unblinded study that were not mentioned. First, and probably foremost, is that this study selectively chose volunteers who were willing to participate in the fairly intense exercise regimen. This significantly limits its applicability to the public at large. This was not mentioned in the news release.
Secondly, this study could not draw conclusions regarding the impact of exercise on developing heart failure in the future. The news release erroneously implied it could.
Third, the article clearly contends that the interventions provide a clinical benefit (“reverse damage to sedentary, aging hearts and help prevent risk of future heart failure”) while the study itself only documents improvements in what are essentially lab values: improvement in oxygen intake during exercise and improved left ventricular compliance (ie. elasticity). Whenever possible, news releases should make it clear how such values may or may not translate to outcomes that make a difference in people’s lives — such as living longer or better.
This news release uses the term “heart aging” without explanation. It’s not clear what it means and it sounds vaguely worrisome, but we don’t think it rises to the level of disease mongering.
The news release mentions the funding sources for the study (NIH and American Heart Association). There are no conflicts of interest listed in the news release or study.
It’s not clear if there are any viable alternatives to exercise for the outcomes addressed in this study. The subjects selected for this study — if they, indeed, have less flexible left ventricles — are potentially comparable to patients with what is called ‘heart failure with a preserved ejection fraction (or, HFpEF; with ejection fracture being a way to measure the efficiency of the heart as a pump). The paper mentions the medication, spironolactone, as ‘the only treatment strategy recommended (class II recommendation) to counteract the debilitating effects of HFpEF.” The news release could have mentioned this alternative, but we won’t dock points for not doing so. We’ll rate it not applicable.
The intervention in question here is aerobic exercise. Widely available.
The news release mentions early research by cardiologists from the same institution documenting stiff left ventricles in middle-aged people who don’t exercise. It’s mentioned that this study is unique in asking the question: can exercise restore heart elasticity in previously sedentary, middle-aged people?
We’ll rate this satisfactory. But really, this is just one of innumerable studies that show exercise is beneficial. It might be measuring the benefit in a novel way but, in the end, it is just suggesting that exercise is good.
This is key problem posed by this news release: Implying that there is damage in an aging heart that can be reversed, without justifying the use of the word ‘reverse.’
Also, the phrase ‘heart aging’ does not come from the study, is not commonly used by either cardiologists or general practitioners, and is potentially misleading for readers.