REF-988 · Staff et al., 2023 · Sports Medicine, Vol. · Paper · PubMed

Long-Term Development of Training Characteristics and Performance-Determining Factors in Elite/International and World-Class Endurance Athletes: A Scoping Review

B+moderate evidenceMeasured on elite to world-class athletesWritten before October 2026, being re-checked

This scoping review mapped studies on how training characteristics and performance-determining factors develop over the long term in endurance athletes, men and women, who went on to reach elite/international (Tier 4) or world-class (Tier 5) level.

Of 16772 items screened across what the abstract calls a 22-year period (1990-2022), 17 peer-reviewed articles qualified, covering athletes from seven sports and seven countries; 109 athletes in all, 27% women and 73% men.

In the ten studies reporting training volume and intensity distribution, most athletes raised their volume year on year in a non-linear way until it plateaued.

In the eleven studies on performance-determining factors, most found gains in submaximal variables (work economy/efficiency, lactate/anaerobic threshold) and in maximal performance indices (peak speed/watt in testing), while VO2max developed inconsistently from study to study. No evidence on sex differences was found.

The authors conclude that long-term studies are scarce and that talent-development practice rests on limited scientific evidence.

Participants

109 athletes across 17 studies, from seven different sports and seven different countries; one quarter women (27%), three quarters men (73%). All reached Tier 4 (elite/international) or Tier 5 (world-class). 11 (69%) of the studies were published during the last decade.

Protocol

Design: scoping review following the Joanna Briggs Institute methodology.
Search: 16772 items screened, 1990-2022 (the abstract describes this as a 22-year period).
Inclusion: peer-reviewed studies describing long-term development of training characteristics and/or performance-determining factors in athletes reaching Tier 4 or Tier 5.
Synthesis: descriptive; ten studies on training volume and intensity distribution, 11 on performance-determining factors. No meta-analysis.
Nature of the evidence: longitudinal, within-athlete descriptions over years (not comparisons between athletes of different levels).

Key Results

Training volume: a non-linear, year-to-year increase was found for most athletes, resulting in a subsequent plateau (ten studies).
Performance-determining factors (11 studies): the majority reported gains in submaximal variables, such as work economy/efficiency and lactate/anaerobic threshold, and in maximal performance indices, such as peak speed/watt in performance tests.
Conversely, the development of VO2max was inconsistent across studies.
No evidence was found regarding possible sex differences in the development of training or performance-determining factors.
Authors' conclusion: a low number of long-term studies is available; existing talent-development practices are built upon limited scientific evidence.

Practical Application

"Once you are already at a high level, what keeps improving over the years?" A scoping review of 17 longitudinal (within-athlete) studies covering 109 athletes who reached Tier 4-5 found that most studies showed improvement in submaximal variables — lactate/anaerobic threshold and economy/efficiency — and in peak test speed/power, while VO2max development was inconsistent across studies. At this level the long-term gains were more reliably found below the ceiling than in the ceiling itself.
Scope: Tier 4-5 only. Inference, not tested here: it is consistent with the engine being developed earlier and the submaximal qualities later, but the review did not study lower tiers and reports no magnitudes or timelines.
"Inconsistent" is not "unchanged": some studies saw VO2max rise, others did not. The abstract gives no numbers.
Volume rose year to year, non-linearly, and then levelled off in most athletes; the abstract gives no hours.
Descriptive only: the review does not show that any training choice produced these changes.

Limitations

Only 17 studies and 109 athletes; many are small case series or single-athlete reports (sample sizes per study are not given in the abstract).
Results are reported as "most studies" — no pooled estimate, no magnitudes, no rates of change.
Seven sports and seven countries are mixed; measurement methods differed and the authors call for high-precision, reproducible measurement.
Survivorship: only athletes who reached Tier 4-5 were included, so nothing can be said about those who trained similarly and did not.
Women were one quarter of the athletes; no evidence on sex differences.
The abstract labels 1990-2022 a 22-year period; it is quoted here as printed.
Written from the abstract and record metadata only (full text not read).
How this entry was checked and changed
Why this level

systematic search, but the 17 included studies are descriptive longitudinal reports covering 109 athletes in total; findings are counts of studies, not pooled effects