About / Research reviewer

Plamen Yankov

Plamen Yankov is a Data Scientist and the founder of Zyra, and has held a personal trainer certificate since 2005. He reviews the research behind every article on zyra.fit: that each study says what the article says it says, that the statistics are read correctly, and that the limits are on the page.

Education

Degree

BSc Computer Science (Machine Learning and Artificial Intelligence), First Class Honours

Institution

Goldsmiths, University of London. The degree is awarded by the University of London; examinations were set by Goldsmiths.

Data science bootcamp

Le Wagon, 9-week hands-on data science bootcamp, in person, Amsterdam, September 2021.

Focus

Machine learning, statistics and data analysis: the tools used to judge whether a result is real.

Sport and fitness certificates

Personal Trainer Certificate

Continental Organization of Registered Fitness Instructors and Teachers (CORFIT), Sofia, Bulgaria, May 2005.

Performance Nutrition Certificate

Continental Organization of Registered Fitness Instructors and Teachers (CORFIT), Sofia, Bulgaria, May 2005.

Plamen Yankov is a former national cycling champion in Bulgaria. The certificates are fitness qualifications, not a medical or dietetic licence.

Why a data scientist reviews fitness research

Most arguments about training and nutrition are arguments about data. How many people were in the study? Was there a control group? Is the difference bigger than the noise? Does a pooled estimate from twenty small trials hold up once you look at how much they disagree? These are statistics questions, and they decide whether a headline is worth repeating.

That is the job here. The articles are written by the Zyra team against the primary papers; the review checks the reading of those papers, number by number.

What a review checks

• Every study is opened. Each cited paper is opened at its PubMed, DOI or journal page. A claim is only kept if the paper says it; where only the abstract could be read, the article cites only what the abstract says.
• The numbers match the source. Sample sizes, group averages, effect sizes and confidence intervals are checked against the paper, including the figures drawn in the charts.
• Who was studied is stated. Trained or untrained, age, sex, dieting or not, weeks or years: the population and duration sit next to every result, because a finding in 12 untrained young men is not a finding about everyone.
• The statistics are read correctly. A pooled estimate is not a guarantee; a wide confidence interval is uncertainty, not an effect; an association in a cohort is not a cause. The wording is checked for each of these.
• The limits come first. Small samples, short trials, funding and what the study could not measure are written into the article, not left out.
• No medical advice. Articles describe what studies found. They are not medical advice, and they never tell anyone what to do about a health condition.

What a review is not

Plamen Yankov is not a physician or a registered dietitian, and the reviews do not stand in for either. They check evidence and statistics, not whether something suits a particular person. If you have a health condition, talk to a qualified professional.

Corrections

If a number, a study or a sentence is wrong, email privacy@zyra.fit. Corrections are made on the page, and the page's reviewed date changes. The formulas behind the calculators are written out on the methodology page, and the papers are collected in the research library.

Articles reviewed (212)