REF-1270 · Litwinowicz et al., 2021 · Sports Medicine · Paper · PubMed · Free full text

What takes pressure off the perineum on the bike?

Standing on the pedals (restored penile oxygen pressure in 6 lab studies) and a no-nose saddle (about 63% less perineal pressure, less stable). Lab markers.

Main caveat: Markers, not symptoms: penile oxygen pressure, blood flow and seat pressure in short laboratory sessions; the authors name this gap themselves.
moderate evidenceMeasured on non-athletes to trained athletes

Litwinowicz and colleagues (Wroclaw Medical University) searched MEDLINE, Scopus, PEDro, CINAHL and CENTRAL to 12 August 2020 for interventional studies in healthy men that tested ways of reducing the load of cycling on the perineum: saddle designs, riding positions, a seat-post shock absorber, padded shorts and the recumbent bike.

They included 22 studies with 601 participants and could pool only one comparison.

Sitting on the saddle lowered transcutaneous penile oxygen pressure by 72.58% on average compared with standing on the pedals, a pooled standardised mean difference of 5.58 (95% CI 3.18 to 7.98) across six studies; single studies showed penile blood flow and penile blood pressure falling while seated, and penile blood pressure back to normal after a 10-minute recovery.

No-nose saddles lowered perineal pressure by 63.24% on average (two studies) and anterior seat pressure by about 71%, kept penile oxygen pressure higher than a standard narrow saddle (a fall of 20.3-22.3% vs 70.4-82.4%), and in one 6-month study of police cyclists went with less urogenital numbness (73% to 18%) — at the cost of lower perceived stability and higher pressure under the sit bones.

Central cut-outs lowered anterior pressure but did not lower total pressure and did not change penile oxygen pressure.

Wider saddles reduced the fall in penile blood flow; a recumbent bike nearly abolished the fall in penile oxygen pressure in one study; padded shorts made no difference; hand position (tops vs drops) did not change anterior pressure, and a 60° trunk lowered total pressure only on a holed saddle.

The authors conclude that no-nose saddles are supported, that standing on the pedals every ten minutes "might be" effective, and that recumbents appear protective but have practical drawbacks.

Our reading: the direction is consistent — less weight on the front of the saddle means better penile perfusion in the lab — but almost everything is an acute marker in short sessions, and the clinical results are two: fewer men with urogenital numbness after 6 months on no-nose saddles in one study without a control group (73% to 18%), and fewer with perineal numbness on an experimental seat with a cutout in the nose in one crossover of 15 (11 vs 2 participants, P < 0.01).

The "every ten minutes" rule is, in the authors' own words, an arbitrary number.

Protocol

Question: strategies to reduce the impact of cycling on the perineum in healthy males; comparator: conventional cycling position and equipment.
Search: MEDLINE (1948 to August 2020), Scopus, PEDro, CINAHL, CENTRAL; manual reference search; last search 12 August 2020; no language or publication-status restriction; peer-reviewed journals only.
Eligibility: interventional studies of healthy men (male subgroup extracted from mixed studies); outcomes: pressure in seat regions, validated sexual-function questionnaires, penile haemodynamics, subjective perineal complaints; exclusion: cardiovascular disease.
Selection: two reviewers independently, a third arbitrating; 3193 records plus 6 from references; 2217 after removing duplicates; 39 read in full; 22 included (n = 601 participants in total); 6 in the meta-analysis.
Included designs (Table 1): 2 randomised trials (29 and 16 participants), 6 crossovers (15-46), 14 before-and-after studies (9-100); laboratory sessions in most.
Risk of bias: ROBINS-I (before-and-after) and RoB-2 (crossover and randomised) by two reviewers; plots in the supplement (not read); blinding of participants not considered; publication bias not assessed because of the small number of studies.
Synthesis: random-effects standardised mean differences in RevMan 5.3 wherever at least three clinically homogeneous studies existed — met only for standing vs sitting.
Funding and interests: "The authors received no specific funding for this work"; all three authors declare no conflict of interest (full text). The Crossref and Europe PMC records list Wroclaw Medical University as funder. No saddle maker is among the authors or funders.

Key Results

StrategyEvidenceResult as reported
Standing vs sitting: penile oxygen pressure6 studies pooledSitting −72.58% on average; SMD 5.58 (95% CI 3.18, 7.98), P < 0.00001
Standing vs sitting: penile blood flow, penile blood pressure1 study eachBlood flow 1.7 to 1.0 ml/min/100 g; penile blood pressure 126 to 76 mmHg after 5 min seated, back to normal after a 10-min recovery
No-nose vs standard saddle: perineal and seat pressure2 studies (perineal); 1 (anterior/posterior)Perineal pressure −63.24% on average; anterior 31 vs 8.99 kPa; posterior 23.4 vs 27.3 kPa; total not different
No-nose vs standard narrow saddle: penile oxygen pressure2 studiesFall of 20.3-22.3% vs 70.4-82.4%
No-nose saddle for 6 months (police cyclists)1 before-and-after, 73 analysedPerineal pressure 20.4 ± 8.9 vs 7 ± 3.2 kPa; urogenital numbness 73% vs 18%; IIEF 29.12 ± 2.4 vs 29.61 ± 1.35
Central cut-out vs standard2 studies (pressure), 1 (penile oxygen)Total pressure not significantly higher (30.3 vs 27.6 kPa); anterior lower (31 vs 26.8 kPa); posterior higher (23.4 vs 27.1 kPa); no penile oxygen difference
Wide vs narrow saddle3 studiesPenile blood flow −19% (wide) vs −84% (narrow) in one
Recumbent vs upright bike1 study (plus 1 reclining position)Penile oxygen fall 2.13% vs 72.5%
Trunk 60° vs 90°; hands on tops vs drops4 studiesAnterior pressure did not differ between tops and drops (2 studies); total pressure lower at a 60° trunk only on a holed saddle (1); tops raised posterior pressure (1); perineal discomfort unchanged (1)
Seat-post shock absorber1 studyLower perineal pressure stationary with oscillation; not significant while pedalling with oscillation
Padded shorts (three pads)1 studyNo significant differences
Perceived stability2 studiesNo-nose and short-nose saddles rated less stable
Heterogeneity: the I² of the standing meta-analysis is not given in the text (forest plot only).
Who ran the pooled studies: five of the six standing-vs-sitting studies share authors (Nayal, Schwarzer, Klotz, Engelmann; Schwarzer, Sommer, Klotz, Engelmann; Sommer, Schwarzer, Klotz, Engelmann in three more, from the reference list); only Cohen and Gross is independent, and several report near-identical seated and standing values (for example 61.1 ± 7.1 vs 16.8 ± 4.1 and 60.4 ± 7.8 vs 18.4 ± 4 mmHg); the review does not discuss whether participants overlap (our reading of Table 1 and the references).
Numbers that do not add up:
The Key Points call the no-nose saddle, standing on the pedals "every few minutes" and the recumbent bike "effective", and the abstract says standing every ten minutes "might be an effective" strategy, while the Discussion says there is "no direct evidence" for standing every ten minutes and only one comparison could be pooled.
The Discussion gives a 71% reduction for the no-nose saddle and the Results 63.24%; the first is anterior seat pressure in one study (31 vs 8.99 kPa), the second perineal pressure averaged over two.
The protruding-nose correlation is r = 0.994 in Table 1 and r = 0.996 in the text.
The padded-shorts figures quoted in the text as perineal pressure (12.6, 12, 12.3 kPa) are the mean total seat pressures in Table 1.
Munarriz et al. studied men with erectile dysfunction suspected to come from cycling, in a review restricted to healthy men, and its CAPSV figures (0.36/0.77 vs 21.57/21.13 cm/s) look like changes from baseline rather than velocities.

Mechanisms

Measured: sitting on the saddle lowers penile oxygen pressure, blood flow and blood pressure within minutes and standing restores them; no-nose saddles move pressure from the front of the saddle to the sit bones.
Authors' interpretation: perineal pressure compresses the pudendal neurovascular bundle (Alcock's canal) and may reduce its blood supply, causing perineal numbness; the area near the pubic symphysis is the most vulnerable, so lowering anterior seat pressure matters most, and at least a 60% reduction in anterior pressure is needed to reduce internal perineal compression (citing an MRI study).The possible link from numbness to erectile dysfunction is why they call perineal protection critical.
Inference: these are acute markers in sessions of minutes; whether they translate into fewer symptoms over months rests on one uncontrolled 6-month study in police cyclists, in which the IIEF score rose from 29.12 to 29.61 ("a small, but significant increase" in the review's words).
Inference: the pooled SMD of 5.58 is very large because seated and standing values differ by roughly 25-55 mmHg with small spreads in the same men; it says the direction is not in doubt, not that the clinical benefit is large.

Practical Application

What takes pressure off the perineum on the bike? Standing on the pedals (restored penile oxygen pressure in 6 lab studies) and a no-nose saddle (about 63% less perineal pressure, less stable). Lab markers.
Stand up regularly (B+, laboratory markers in men): standing reversed the seated fall in penile oxygen pressure in every pooled study, and in a survey of 3,932 men standing more than 20% of the time went with lower odds of genital numbness (REF-1268, OR 0.4).Standing every ten minutes is advice the authors repeat in their conclusion ("might be an effective" strategy) while finding "no direct evidence" for it and calling 10 min "an arbitrary number"; how often and how long to stand is untested. Not from this paper; the base's own practice: any regular out-of-the-saddle spell is reasonable.
A no-nose saddle has the most support in this review (lower perineal pressure and better penile oxygen pressure in the lab, and less urogenital numbness after 6 months in one uncontrolled study of police cyclists; healthy men, not men with persistent numbness), with trade-offs: less perceived stability, more pressure and discomfort under the sit bones, and some riders return to a nosed saddle (3 of 90 police officers after six months in the study the authors cite).
A central cut-out is not the same thing: it lowered pressure at the front but not overall and did not change penile oxygen pressure; in competitive women a cut-out went with higher perineal pressure (REF-1273).
Persistent numbness, pain or any change in erections goes to a clinician. Not from this paper; the base's own practice.

Limitations

Markers, not symptoms: penile oxygen pressure, blood flow and seat pressure in short laboratory sessions; the authors name this gap themselves.
Weak designs: 14 of 22 studies are before-and-after; two are randomised; most are small (9-100 participants).
One pooled analysis, from six studies, five of them with overlapping authors; heterogeneity not reported in the text; publication bias not assessed.
Laboratory setting: terrain, vibration, varying workloads and long rides are largely missing (the authors' limitation); no study of correcting bike fit or riding posture was found.
Scope: healthy men only; one included study was of men with erectile dysfunction, against the stated criterion.
Reporting inconsistencies listed under Key Results.
Funding and conflicts: no specific funding; no conflicts declared.
How this entry was checked and changed
Why this level

read from the full text (Europe PMC, open access, CC BY 4.0). One step below the rubric's A- line (an SR/MA "with serious heterogeneity or mostly small trials") because the inputs are mostly short, small, uncontrolled before-and-after laboratory sessions, the only pooled estimate is a marker (penile oxygen pressure), no symptom or erectile-function outcome was pooled, five of the six pooled studies share authors, and publication bias was not assessed

Full text (checked 2026-10-27)
22 studies qualified for the systematic review and 6 were used in the meta-analysis; in total, the studies encompassed 601 participants (full text)
On average, sitting on the saddle reduced transcutaneous penile oxygen pressure by 72.58%; the meta-analysis showed an effect size of 5.58 (95% CI 3.18, 7.98), P < 0.00001, Z = 4.55 (full text)
Penile blood pressure decreased from 126 to 76 mmHg after 5 min of sitting on the saddle and returned to normal after a 10-min recovery period (full text)
The average reduction of perineal pressure using a nose cutout saddle (compared with standard saddle) was 63.24% (full text)
A no-nose saddle reduced occurrence of urogenital numbness over 6 months from 73 to 18% (full text)
Cycling on a recumbent bike: a 2.13% reduction of penile oxygen pressure vs 72.5% on an ordinary bike (full text)
On standing every ten minutes: "10 min is an arbitrary number for which we did not find justification in current literature" (full text)
"The authors received no specific funding for this work"; Kamil Litwinowicz, Marcin Choroszy and Anna Wróbel declare that they have no conflict of interest (full text)