ATC 337: Swim Erg vs Lap Swimming For Triathlon Performance, When Can You Cease Strength For More Sport-Specificity (and Still Maintain Gains), Marathon Transfer To Ironman Run, and More

February 11, 2022


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Study Mention: 

The Effects of Resistance Training Cessation on Cycling Performance in Well-Trained Cyclists

“Supplementary (i.e., concurrent) resistance training can enhance cycling performance among competitive cyclists. However, a lack of knowledge exists about the retention (decay profile) in mechanical muscle function and cycling performance after concurrent resistance and endurance training. The present exploratory intervention study investigated the effect of 6 weeks of resistance training cessation when preceded by 8 weeks of concurrent resistance and endurance training on mechanical muscle function and cycling performance in 9 male well-trained competitive cyclists (V[Combining Dot Above]O2max = 66 ± 7 ml·min−1·kg−1). Cyclists performed periodized resistance training targeting leg and core muscles for 8 weeks as a supplement to their normal endurance (cycling) training. This was followed by 6 weeks of endurance training only (retention period) leading up to the start of the competitive season. Maximal leg extensor power, isometric leg extensor strength (maximal voluntary contraction [MVC]), rate of force development (RFD), and long-term cycling performance (2-hour submaximal cycling at 55% of Wmax), followed by 5-minute max cycling were evaluated. After 8 weeks of concurrent resistance and endurance training, leg extensor power, MVC, and RFD increased by 12, 15, and 17%, respectively while mean power output (W) during 5-minute max cycling increased by 7% (p < 0.05). Training-induced gains in Maximal Voluntary Contraction and 5-minute max cycling power were retained after 6-week cessation of resistance training (p < 0.05). These findings indicate that competitive cyclists can focus on cycling training alone for at least 6 weeks leading up to competition without losing attained gains in maximal muscle strength and cycling performance achieved by preceding periods of concurrent resistance training.”

The question that athletes and coaches might have is “How long should I strength train during my training cycle, and/or when should I stop ST and focus on sport specificity?” This gives some valuable insight…

What the coaches say:

What this study investigated and found:
  • Subjects were 9 competitive Danish male well-trainer sub-elite cyclists.
    • Note: small sample size and no control
    • “Although most research generally reports positive effects of concurrent resistance and endurance training on both short-term and long-term cycling performances, limited knowledge exists about the retention of mechanical muscle function and cycling performance when concurrent resistance training is removed from the training schedule.” 
  • What they did:
    • 8 week strength training intervention. 
    • 6 week no strength (but maintaining cycle training).
    • Strength sessions of 60 minutes including squat, abdominal crunch with olympic weight bar, unilateral leg press, back extension with handheld weight(s), and planks. 
    • “A rest time of 3 minutes between successive sets was used for squat and unilateral leg press exercises to emphasize the improvement of maximal strength and RFD because moderate to long rest intervals should demand heavier loads and faster concentric phases than using shorter rest intervals (11,20). By contrast, 1 1/2-min rest periods were used for the less strenuous exercises (abdominal crunches, back extension, and plank).” 
    • The volume and intensity of the endurance (cycling) training were kept stable throughout the study period.
  • Results:
    • They gained and retained a boost in 5-minute maximal cycling power coming off a 2hr submax ride.
    • Another study looked at something similar but had different protocols and all the strength training gains that had been observed tended to decrease showing a detraining effect. 
    • “This study demonstrates that concurrent resistance and endurance (cycling) training can elicit improvements in mechanical muscle function and cycling performance, respectively, in highly trained competitive cyclists. Perhaps more importantly, maximal muscle strength and cycling performance may be maintained in this athlete population for at least 6 weeks after withdrawal of resistance training.” 
    • The practical implications are that coaches/ cyclists can choose to either maintain or remove resistance training when preparing for competition.
    • The study authors note that a “single weekly session of heavy resistance training during 25 weeks of the competition season seems effective of retaining the positive effects from preceding periods (12 weeks) of a heavy resistance training intervention period among well-trained cyclists (41).”
    • The subjects of this study did not gain body mass during the 8-week strength training intervention period, i.e. no muscle hypertrophy occurred. Instead gains seem in part due to increased neural drive.
    • They also speculated that there could have been in a shift from type IIx to type IIa myofibers to led to gains that were retained without hypertrophy taking place.
      • Type IIa are oxidative and more fatigue-resistant compared to type IIx fibers.

Some take-homes and limitations:

  • Cyclists are a different beast than triathletes, runners, etc. So how would this carry over in different endurance sports?

Grace asks:

Swim erg vs lap swimming for real-life triathlon swim performance?

Hi guys! Ever since C entered our world swimming laps in the pool has become exponentially more difficult and a pain in the butt. Plus it’s just hard to get to the pool—as Lucho has talked about on recent shows, it ends up being such a trek!
I bought a Vasa swim Erg machine last year, and love it–and no, it is NOT an easy workout. I want to use this for the bulk of my swim training for triathlon this year, but is that a risk? In 2022, I plan to do a couple Olympic distances and at least one 70.3, all this summer. I’ve heard people say that the crossover is incredibly specific, and that the swim erg can be a solid substitute for actual pool swims, but how accurate is this? Should I trust that advice and feel comfortable mostly sticking to the erg for training and not stress over the pool so much? I still want to get to the pool on occasion but not like I would have before, when it was swimming 2-3x a week. Now it would be pool swims 2-3x a month + erg multiple times a week. What do you think? Is it a risk? Are there any studies or evidence in support of the swim erg for real-life crossover in swimming? Thanks!

What the coaches say:

  • The swim erg has been around since late 80s / early 90s, but there is minimal literature on the effectiveness of a training intervention utilizing a swim ergometer for swim training crossover.
  • Nothing on dryland can truly replace the sensation of water, but the erg gives a swim-specific strength workout.
  • When options are limited training on something like an erg is better than nothing at all! Do what you can; control what you can.
  • We’d suggest using the erg multiple times a week but still trying to get in the pool for a real swim once a week if possible.

2021 Study: The Effects of Anaerobic Swim Ergometer Training on Sprint Performance in Adolescent Swimmers

  • Participants in the ERG group experienced a greater increase in the speed of the 4th 50m effort following the intervention period compared to the pool swimming (PST) group
  • Participants in both groups experienced a significant increase in every measure of power output
  • The similarity in training response to ERG and PST SIT over 4 weeks suggests that the swimming ergometer may be utilized as a dryland training modality in swimmers

What the erg can potentially do for your swimming:

  • Increase stroke rate.
  • Improve power and distance per stroke, with less effort.
  • Movement pattern that translates to the water.
  • Can help with technique, keeping high elbow and good form gives direct feedback.
  • Allows you to work on biomechanics without having to struggle with breathing like some will in the water.
  • How much is needed?
    • Just 20-30min can be incredibly effective.
    • Ideally a training regimen would include weekly volume of 2-4x @ 20-40min each.
  • However, how does this translate to long-course endurance swims? We know that it can help power and short duration, but what about all the triathletes swimming non-stop longer distances in races? Evidence seems to be anecdotal.
  • More resources:

Dave F. asks:

When you’re 18 weeks out…

Hi guys,

Firstly love the show! I am a relative newbie into triathlon this is my fourth year of training and racing.

My only race in 2021 was my first marathon (3hr10min) the beginning of December (avg; 60km/week training for 8 weeks).

Being 35 and with a young family, my wife and I have decided that if I would like to compete in an Ironman, now is the time! So I have signed up to Port Macquarie (Australia).

18 weeks out at the time of this email (sent 12/27/21), I have started following a training peaks program (10-15 hours per week). Would love a coach but we just can’t afford it right now.

Example week: threshold sessions (SBR) Monday and Tuesday; long run Wednesday; and two long rides + brick of a weekend to fit in busy schedule. I also do 2-3 strength sessions plus some easier swimming other days.

Going this pretty much alone, my question is around pacing. Having just completed the marathon, is it reasonable to say I will hold my run fitness doing avg. 40-50km/week. Is 3hr30min (5min/km) a reasonable target? Or should I be more ambitious?

I continued cycling 2 times per week during marathon build, but no swimming. Did a 160km ride week after marathon no problem. Plan this far out, would be to get fit enough to hold high zone 2 for the ride.

The swim, is the swim.

For reference:
70.3 pb 4hr35min
Slow swimmer
Cycling for ~8 years >300FTP
Played football growing up

Really appreciate all the help!

What the coaches say:

  • This adjustment seems right (i.e. ~20min drop), but a lot of variables that can affect this so it’s impossible to predict.
  • High Z2 on the bike affects the run more than low/mid Z2; tradeoffs.
  • Running a 3:10 on fairly minimal training for the marathon was a fantastic result, shows running strength. (And that there is a lot more potential for a faster marathon performance in the future!)
  • Make sure FTP is on point, Z2 is a % of FTP so the higher FTP is the higher your Z2 can be for better performance.
  • 3:30 may no be competitive in this particular Ironman, would need <3:20; while a 5-hour bike is competitive.
  • So in the race: bike more cautious, and go for it on the run! However, if you end up cooking it on the bike and go a too hard then you’ll need to dial it back on the run. All a juggling act.
  • With Lucho: he is using mileage (not time) for his Ironman training.
  • When running, look for the hardest sustainable effort for the distance remaining.
  • Do a brick/big day of a 4-5 hour bike with high percentage at Ironman effort followed by a 1-hour run at about 20 seconds faster per mile; 10-15 seconds faster per km from your IM goal pace (for him 5:00/km).

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