Study note • PMID 36572038
Fasted Sprint Interval Training Results in Some Beneficial Skeletal Muscle Metabolic, but Similar Metabolomic and Performance Adaptations Compared With Carbohydrate-Fed Training in Recreationally Active Male.
Low risk + high feasibility for most athletes.
ELI5
In plain language
Endurance training in fasted conditions (FAST) induces favorable skeletal muscle metabolic adaptations compared with carbohydrate feeding (CHO), manifesting in improved exercise performance over time. (randomized trial; recreational participants).
The abstract doesn’t indicate a clear change in VO₂max, Lactate threshold under the tested conditions. Treat this as a signal, not a guarantee; confirm methods and context in the full paper.
Takeaways
What the abstract suggests
- • Study question: Endurance training in fasted conditions (FAST) induces favorable skeletal muscle metabolic adaptations compared with carbohydrate feeding (CHO), manifesting in improved exercise performance over time.
- • The abstract doesn’t indicate a clear change in VO₂max, Lactate threshold under the tested conditions.
- • Population: recreational participants.
- • Protocol cues (title/abstract): 3 weeks.
Protocol
Protocol (as reported)
- • Intervention/exposure: aerobic, endurance (vs comparison group).
- • Dose/time/duration cues in abstract/title: 3 weeks.
- • Outcomes: VO₂max, Lactate threshold.
- • Replication note: abstracts often omit adherence and timing; confirm details before changing training or supplementation.
Fit
Who it helps, and who should skip it
Who it helps
- • Athletes similar to the study population (recreational participants) working on endurance.
- • Athletes who can measure VO₂max, Lactate threshold with a repeatable workout or time-trial effort.
Who should skip
- • If you have symptoms or conditions that make the intervention risky, get professional guidance.
- • If you’re near race day and can’t safely test, defer the experiment.
Methods
What the study actually did
- • Design: randomized trial (double-blind).
- • Population: recreational participants.
- • Comparator: comparison group.
- • Outcomes measured: VO₂max, Lactate threshold.
- • Protocol cues mentioned: 3 weeks.
- • Source: PubMed PMID 36572038 (2023) — International journal of sport nutrition and exercise metabolism.
Results excerpt
What the abstract reports
“Endurance training in fasted conditions (FAST) induces favorable skeletal muscle metabolic adaptations compared with carbohydrate feeding (CHO), manifesting in improved exercise performance over time.”
Note: excerpts are short; for full context, read the paper.
Limits
Limitations & bias
- • Abstract-only summaries can miss critical details (population, protocol, adherence, and context).
- • Single studies often don’t generalize to your event, history, and training load; treat results as a starting point.
- • If your context differs (elite vs recreational; cycling vs running), adjust expectations and be conservative.
- • This is performance information, not medical advice.
Coaching beta
Get a plan that adapts to your life.
Join the 26weeks.ai TestFlight beta for adaptive coaching, recovery-aware adjustments, and race-week reminders.
Keep going
Performance Science Lab
Research-backed protocols and evidence grades for endurance performance — built for athletes.
Endurance performance research
Endurance is built by repeatable work you can recover from — not by heroic weeks you can’t sustain.
Caffeine for endurance performance: a practical protocol
Evidence-informed protocol: Caffeine for endurance performance: a practical protocol. Practical steps, who it helps, and what to watch out for.
VO₂max research for endurance athletes
A ceiling metric: useful, but endurance performance is usually limited by durability and pacing.
Lactate threshold research for endurance athletes
Threshold is 'how fast you can go for a long time' — where most endurance races are decided.