REF-1469 · Zandonai et al., 2019 · Scandinavian Journal of Medicine & Science in Sports · Paper · PubMed

Should a snus user skip it on race morning?

Not answered: 16 snus users lasted longer with snus after 12 h off than when sated (24.1 vs 20.9 min), but no trial was snus-free. From the abstract.

Main caveat: Abstract only; repository copies sit behind bot checks or refused the request, so methods and tables were not read.
limited evidenceMeasured on trained athletes

Zandonai and colleagues investigated the effect of snus on aerobic performance in athletes after abstinence or in a sated nicotine state. Sixteen male snus-using athletes did an exercise to exhaustion at a constant 80% VO2max in two sessions, one after 12 h of overnight abstinence and one in satiety; a 1-g portion of snus (about 8 mg/g nicotine) was given 25 min before each.

Nicotine and cotinine confirmed the conditions. Time to exhaustion was longer after abstinence (24.1 ± 10.7 min) than in satiety (20.9 ± 8.0 min; P = 0.0131). At baseline, abstinence came with higher muscle tissue oxygenation (+4%) and changed metabolic and cardiovascular values against satiety.

The authors suggest snus at test time may relieve these withdrawal changes and so lengthen time to exhaustion. Our reading: the comparison is snus after a break against more snus on top of normal levels.

It cannot tell apart a withdrawal being relieved, a larger acute nicotine rise, or a sated state that was worse; and it does not show that a dependent athlete rides worse abstinent, because nobody rode abstinent without snus.

Protocol

Participants: n = 16 male snus-using athletes; sport, level and usual use are not in the abstract.
Conditions: two sessions in random order: 12-h overnight abstinence and satiety; both with 1 g snus (about 8 mg/g nicotine) 25 min before the test.
Test: exercise to exhaustion at a constant load of 80% VO2max, set from a maximal incremental test.
Measures: time to exhaustion, global RPE, cardiovascular and metabolic responses, muscle and cerebral oxygenation (NIRS), nicotine and cotinine.
Funding and interests: PubMed lists the World Anti-Doping Agency as grant funder; no conflict statement in the record.

Key Results

OutcomeAfter 12-h abstinence + snusSatiety + snusP
Time to exhaustion (min)24.1 ± 10.720.9 ± 8.00.0131
Printed change: +13.1% for time to exhaustion. The two means differ by about 15% against satiety (our arithmetic); the printed figure may be a mean of individual changes.
Baseline, abstinence vs satiety: muscle tissue oxygenation +4%; metabolic and cardiovascular values significantly raised (values not in the abstract).
Not in the abstract: RPE values, a snus-free comparison, order effects, sport and fitness.

Mechanisms

Measured: longer time to exhaustion when snus followed abstinence; different baseline values after abstinence.
Authors' interpretation: snus administered at test time might relieve withdrawal changes and yield an increase in time to exhaustion; they also describe an increase of performance due to snus in the abstinent condition.
Inference: the design has no snus-free arm, so "withdrawal lowers performance" and "nicotine is ergogenic" are both untested here. A trained-cyclist trial in non-users found no gain from nicotine (REF-1461).

Practical Application

Should a snus user skip it on race morning? Not answered: 16 snus users lasted longer with snus after 12 h off than when sated (24.1 vs 20.9 min), but no trial was snus-free. From the abstract.
Race week: not from this paper; the base's own practice: do not choose race week or race morning for a first nicotine-free day. That rests on withdrawal in general and is not shown by this trial.
Never a race dose: this does not show that nicotine makes anyone faster, whatever the authors' wording. Not from this paper; the base's own practice: do not present it as a pre-race aid. Heat adds its own risk (REF-1462, measured in non-users).
What it does not show: abstinent performance without snus; effects in smokers, vapers or pouch users; women; a race; whether a 13% longer time to exhaustion would mean anything in a time trial.

Limitations

Abstract only; repository copies sit behind bot checks or refused the request, so methods and tables were not read.
No nicotine-free or placebo condition; abstinence is unblinded, and an expectation effect is possible.
Time to exhaustion: wide SDs (24.1 ± 10.7 min) and poor match to a race.
Who was measured: male snus users; sport and level unknown.
Printed percentage does not match the means by simple arithmetic.
Funding and interests: WADA grant per PubMed; no statement in the record.
How this entry was checked and changed
Why this level

(from the abstract) — a crossover with at least 15 participants would reach the rubric's B+, held one step down: no nicotine-free or placebo arm, abstinence cannot be blinded, and time to exhaustion is a variable test