We know muscle energy recovery got better, but we don’t know if it’s because there are more mitochondria, bigger ones, or just ones that work better.

Scientific Claim

In obese adults with reduced GH, the improvement in phosphocreatine recovery following tesamorelin treatment may reflect enhanced mitochondrial function, but the study does not determine whether this is due to increased mitochondrial number, size, or efficiency.

Original Statement

“No study to date has addressed whether this reflects an increase in mitochondrial number, size, density, efficiency, or subcellular localization, and clearly further mechanistic physiology studies will be needed.”

From study:The effects of tesamorelin on phosphocreatine recovery in obese subjects with reduced GH.

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

definitive

Can make definitive causal claims

Assessment Explanation

This is a direct statement from the authors about the study’s limitations. It is factually accurate and appropriately stated without overreach.

Evidence from Studies

Supporting (1)

The effects of tesamorelin on phosphocreatine recovery in obese subjects with reduced GH.

Randomized Controlled Trial

Human

2014 Jan

The study found that a drug called tesamorelin helped obese people with low growth hormone recover energy faster after exercise, which suggests their muscle mitochondria are working better — but it didn’t figure out if that’s because they made more mitochondria, bigger ones, or just more efficient ones.

Contradicting (0)

No contradicting evidence found

Source Study

The effects of tesamorelin on phosphocreatine recovery in obese subjects with reduced GH.

Score: 61

DOI: 10.1210/jc.2013-3436

Similar Assertions

Because so few people finished the study and the muscle energy didn’t improve much more in the drug group than the placebo group, we can’t say for sure the drug caused the improvement.

94%

Before starting the study, both the drug group and the placebo group had the same muscle energy recovery ability, so any later differences weren’t due to starting out differently.

86%

In a 12-month randomized, double-blind, placebo-controlled trial, tesamorelin improved mitochondrial oxidative capacity in obese adults with reduced growth hormone secretion, as measured by enhanced phosphocreatine recovery after exercise, with improvements strongly associated with increased IGF-I levels.

83%

The muscle energy improvement wasn’t because people lost weight or got more active — it seemed to be linked directly to IGF-I levels instead.

83%

When obese people with low growth hormone took a drug called tesamorelin for a year, their muscle energy recovery got better, which means their muscle cells may have become better at making energy.

80%