Exercises That Boost Growth Hormone (Backed by Research)

Two men walk into a gym. One does a 6-second all-out sprint, the other does 30 seconds.

Same bike. Same effort. The 30-second man’s growth hormone peaks at 18.5 µg/L. The 6-second man’s peaks at 4.0.

That’s a 450% difference from 24 extra seconds of work.

I find that number genuinely useful, because it tells you the GH response isn’t about “working hard.” It’s about crossing a specific physiological line — and most guys in the gym never cross it.

But I need to give you the other half straight away, because it’s the part every training article leaves out.

In a 15-week study, men trained one arm in a low-hormone state and the other arm in a high-hormone state — identical arm work, but one followed by heavy leg training to spike GH and testosterone. The high-hormone arm grew 10%. The low-hormone arm grew 12%.

The spike did nothing. If anything the no-spike arm did marginally better!

So this article is going to do two things. Show you exactly which exercises produce the biggest, most reliable GH response — and be honest about what that response is actually good for.

Spoiler: it’s real and it matters. Just not for the reason you’ve been told.

Related reading: training is one of four main levers. For the complete framework — sleep, fasting, body fat and testing — see our pillar guide on how to increase HGH naturally.

Exercise	Why it ranks here	Do it like this
130-second bike or rower sprint Highest	The largest documented acute response of any exercise. Peak GH of 18.5 µg/L, and it stays elevated for 90–120 minutes.	4–6 rounds all-out, 3–4 min passive rest
2Back squat Very high	More muscle mass under heavy load than any other lift, plus an enormous metabolic cost.	4 × 8–10 at 75–85% 1RM, 90 sec rest
3Deadlift Very high	Entire posterior chain under maximal tension. The biggest systemic demand of any barbell lift.	4 × 5–8, 2–3 min rest on heavy sets
4Sled push / prowler Very high	Sustained maximal effort with no eccentric loading — brutal metabolically, and unusually easy to recover from.	6–8 × 20–30 m, walk-back recovery
5Front squat High	Slightly less absolute load than a back squat, noticeably more metabolic and core demand.	4 × 8, 60–90 sec rest
6Hang clean / power clean High	Explosive, full-body, high neural and metabolic demand from the floor up.	5 × 3–5, stop when technique slips
7Walking lunge High	Large muscle mass, long time under tension, and a savage metabolic response for a simple movement.	3 × 20 steps loaded, 60 sec rest
8Bent-over row High	The biggest upper-body pull — legs, back and core all loaded at once rather than an isolated arm movement.	4 × 8–10, 60–90 sec rest
9Loaded carry High	Full-body tension held for time, and one of the best-tolerated hard movements for older lifters.	4 × 40–60 m heavy, 90 sec rest

How this ranking was built — and its limits. Very few studies compare specific named lifts head-to-head for growth hormone response. What the research does establish is that muscle mass recruited and metabolic stress drive it, so this list is ranked on those principles rather than on nine separate trials. Anyone quoting a precise GH figure for the bent-over row is inventing it.

Notice what’s missing: bicep curls, lateral raises, leg extensions, calf raises. Isolation work belongs in a program — it just isn’t a growth hormone driver. And remember the acute spike supports fat metabolism, connective tissue and recovery rather than building muscle directly, so pick these lifts because they’re excellent training, not because of the hormone.

First, the Uncomfortable Finding

Let’s clear this up before we get to protocols, because it changes how you should read everything below.

For decades, the assumption in both gyms and research was straightforward. Train hard, spike growth hormone and testosterone, grow more muscle.

That assumption has not survived testing.

The one-arm experiment

Researchers at McMaster University designed an elegant study. Twelve young men trained their elbow flexors for 15 weeks — each arm separately, on different days, under deliberately different hormonal conditions.

Low-hormone condition: isolated arm curls only. No meaningful GH or testosterone rise.

High-hormone condition: the identical arm workout, immediately followed by a high volume of leg resistance work to drive a large hormonal spike.

Same arm. Same reps. Same load. Same person. Only the hormones differed.

Result: muscle cross-sectional area rose 12% in the low-hormone arm and 10% in the high-hormone arm. No statistically significant difference, and strength gains matched too.

The authors’ conclusion was blunt: exposing loaded muscle to acute exercise-induced hormone elevations does not enhance hypertrophy or strength.

It’s been replicated

This wasn’t a one-off. A separate 12-week study measured post-exercise GH, free testosterone, IGF-1 and cortisol, then looked for correlations with actual gains.

There were no significant correlations between exercise-induced GH elevation and gains in lean body mass or leg press strength.

A 2024 review in Exercise and Sport Sciences Reviews summarised this literature under a title that says it all: Hormones, Hypertrophy, and Hype.

What this does and doesn’t mean

It does not mean growth hormone is useless. It doesn’t mean hard leg training is pointless, and it certainly doesn’t mean you should stop doing squats.

It means one specific thing: the acute post-workout GH spike is not the mechanism that builds muscle. Muscle growth is driven by mechanical tension, training volume and progressive overload, working through local signalling inside the trained muscle.

The researchers put it plainly — there’s no evidence that transient exercise-induced GH changes produce anabolic effects in people with normal GH levels. Pharmacological GH helps clinically deficient patients. That’s a different situation entirely.

So why write an article about exercises that boost GH? Because the hormone does plenty of other things, and the training that raises it is excellent training regardless.

Let’s look at what it actually does.

So Why Train for Growth Hormone At All?

Once you stop treating GH as a muscle-building hormone, its real job becomes clearer — and arguably more relevant to men over 35.

Fat metabolism. GH is strongly lipolytic. It mobilises stored fatty acids for fuel, and this effect is well established rather than contested.

Connective tissue. Tendons, ligaments, cartilage and skin all depend on GH-driven collagen synthesis. If you’re 45 and your joints complain more than your muscles do, this matters.

Recovery and tissue repair. GH supports the repair processes that let you train again sooner.

Bone density. Ongoing bone remodelling and mineral retention.

Systemic vitality. Energy, sleep quality, body composition, and the general sense of functioning well that men notice slipping in their forties.

Here’s the reframe that makes this article worth your time.

Don’t train to spike GH so you’ll build muscle. Train hard because that builds muscle — and take the GH response as a genuine bonus for your body composition, joints and recovery.

The good news is that the protocols are the same either way.

What Actually Triggers the GH Response

Four variables determine whether your session produces a meaningful spike or essentially nothing.

1. Intensity — and a specific threshold

This is the big one. Research on exercise-induced GH points to an intensity threshold rather than a gradual dose-response.

Working above your lactate threshold appears to be the trigger, with roughly 10 minutes above it producing the strongest response.

Below that line, the response is minimal. This single fact explains why a 45-minute jog at conversational pace does almost nothing for growth hormone while 12 minutes of intervals does a great deal.

2. Duration of the effort

The sprint data makes this vivid. A 30-second maximal sprint produced peak GH of 18.5 µg/L versus 4.0 µg/L after a 6-second sprint — over 450% higher.

GH also stayed elevated for 90–120 minutes after the 30-second effort, compared with about 60 minutes after the 6-second one.

The control trial, with no sprint at all, produced no elevation above baseline at any point.

So very short maximal efforts — the 5–8 second bursts common in some training styles — barely move the needle. You need sustained maximal work.

3. Muscle mass recruited

More muscle under load means more metabolic disturbance means more GH. Squats, deadlifts, presses and rows produce responses that isolation work simply doesn’t.

This is also why the leg-training arm of that McMaster study reliably spiked hormones — big muscles, big response. It just didn’t help the biceps grow.

4. Metabolic stress

The burn is part of the signal. Hydrogen ion accumulation and the metabolic disturbance of hard, short-rest work appear to be primary drivers.

Worth a caveat though: one study found no correlation between blood lactate concentration and GH area under the curve, so lactate itself may be a marker rather than the cause. The relationship is messier than the popular version suggests.

One thing that varies enormously

Individual response to identical protocols varies hugely. The sprint researchers specifically flagged large inter-individual variation in GH response to the same 30-second effort.

Some men are simply bigger responders than others. Don’t assume your session failed because you don’t feel what someone else describes.

Sprint Intervals: The Biggest Acute Spike

If you want the single most reliable GH stimulus available, this is it. A single 30-second maximal cycle sprint produces a marked GH increase that researchers describe as at least as reproducible as pharmacological stimulation.

That’s a striking comparison. One brutal half-minute rivals a clinical drug test for reliability.

The protocol that works

• 4–6 rounds of 30-second all-out efforts
• 3–4 minutes recovery between rounds
• Bike, rower, assault bike, or hill sprints
• Twice a week is plenty alongside lifting

Total working time is two to three minutes. Total session time is under 25 minutes.

Take passive recovery, not active

Here’s a detail almost nobody gets right.

Research comparing active versus passive recovery between high-intensity intervals found that active recovery reduces the metabolic stimulus, and with it the hormonal response.

So the instinct to spin easy between sprints is working against you. Stop, sit, breathe, go again.

More sprints don’t stack linearly

This one surprised me, and it’s practically useful.

When researchers had men perform two 30-second sprints separated by 60 minutes, GH was still elevated before the second sprint — and the second sprint produced no further increase.

You can’t simply pile on more sprints for more hormone. Once the system is firing, additional stimulus in the same window gives diminishing returns.

Which argues for quality over quantity: four hard sprints beat ten mediocre ones.

A note on running sprints

Everything above used cycle ergometers, because that’s what labs can standardise safely.

Hill sprints and rowing produce similar metabolic demands. Flat-ground maximal running sprints carry real hamstring injury risk for men over 35 who haven’t sprinted in a decade — build up gradually, or use a bike.

Resistance Training: How to Structure It for GH

The lifting variables are well studied, and the hierarchy is clear.

Rest intervals matter most

This is the biggest single lever in a lifting session.

In trained men, 60-second rest between sets produced GH concentrations 64% higher than 120-second rest immediately post-exercise. Same lifts, same loads — different clock.

Classic work by Kraemer and Ratamess found the same pattern: 10RM loads, three sets per exercise, one-minute rest produced large GH increases.

Load has to be meaningful

Light weights for high reps produce a minimal GH response. You need moderate-to-heavy loads that create real mechanical and metabolic demand.

The practical range is roughly 70–85% of your one-rep max, taken to within a couple of reps of failure.

Choose big compound movements

Squats, deadlifts, front squats, presses, rows, weighted carries. More muscle mass under load, bigger response.

Curls and lateral raises have their place in a program. They’re not GH drivers.

A session that does the job

• 4–5 compound exercises
• 3–4 sets each, 8–12 reps
• 60–90 seconds rest
• 45 minutes, phone in the bag

That last point isn’t a joke. If you’re resting three minutes because you got distracted between sets, you’ve converted a metabolic session into a strength session.

Both are legitimate. Just know which one you’re doing.

The honest caveat on short rest

I’d be misleading you if I stopped there.

Research on long-term muscle growth has not found that shorter rest periods produce superior hypertrophy. One well-known analysis found the opposite — longer rest allowed more total volume and slightly better gains.

So short rest maximises the hormone response and longer rest may build slightly more muscle. Given what we established at the top of this article, prioritise the training outcome, not the hormone.

My practical compromise: use 60–90 seconds on accessory and metabolic work, take the full three minutes on your heavy main lifts.

Combining Sprints and Weights in One Session

Here’s a finding worth knowing if you’re time-constrained.

Research examining a Wingate sprint combined with high-intensity circuit weight training found the combination produced a significantly higher GH area under the curve and higher peak GH than either the sprint or the circuit alone.

Order appeared to matter, with the circuit-then-sprint sequence outperforming the reverse. Treat that specific detail as provisional — it comes from a smaller dissertation study rather than a large trial.

The practical takeaway is sound either way. Finishing a resistance session with a short, brutal conditioning piece stacks the metabolic stimulus.

Two or three minutes of all-out work at the end of a lifting session is a genuine multiplier. It also happens to be excellent conditioning.

What Doesn’t Work

Worth being direct about the things men commonly believe are helping.

Steady-state cardio. Below the lactate threshold, the GH response is minimal. Zone 2 work has real cardiovascular and metabolic benefits — it just isn’t a GH intervention.

Very short bursts. Those 6-second efforts produced 4.0 µg/L versus 18.5 for 30 seconds. If your intervals are 10 seconds long, you’re leaving most of the response on the table.

Light weights, high reps, long rest. Minimal load, minimal metabolic stress, minimal response.

Isolation-only sessions. An arms day won’t produce a meaningful systemic hormone response, though the McMaster study suggests your arms don’t care.

Long, easy sessions. Duration doesn’t substitute for intensity here. Ninety minutes of moderate work produces less GH response than fifteen minutes of genuinely hard work.

Active recovery between intervals. Covered above — it dampens exactly what you’re trying to create.

The Adaptation Problem Nobody Mentions

This one’s genuinely interesting and I’ve never seen it covered in a consumer article.

Your GH response to a given stimulus shrinks as you adapt to it.

Six weeks of sprint training was found to decrease the GH response to sprinting. Your body becomes more efficient at the task, so the same effort produces less metabolic disturbance and less hormonal disruption.

Interestingly, several resistance training studies over 3–8 weeks found no change in the magnitude of the GH response. So the effect may be more pronounced with sprint-type work.

What to do about it

Don’t panic, and don’t chase the spike into overtraining.

Progress the stimulus. More resistance on the bike, faster target times, more load on the bar. Adaptation means the old stimulus is now easy, so make it hard again.

Rotate modalities. Bike sprints for six weeks, then rower, then hill sprints, then sled pushes.

Accept it as a good sign. A shrinking hormonal response to a fixed workload means you’ve got fitter. That’s the actual goal.

There’s a broader point here. The adaptation is the win, not the hormone. If you find yourself adding sessions purely to keep the spike large, you’ve inverted the priorities.

Does the Response Decline With Age?

Partly, and it’s worth understanding what changes.

Your baseline GH output falls substantially with age — largely tracking the collapse in deep sleep that happens between your twenties and your late forties. We covered that mechanism in detail in our guide to how sleep affects HGH production.

The exercise-induced response still works in older men, but from a lower starting point and generally with smaller absolute peaks.

Three practical adjustments after 40:

Prioritise the fundamentals over the spike. Your deep sleep is doing far more for your daily GH output than any single workout. Training is a supporting act.

Manage recovery harder. Chronic overreaching raises cortisol, which is directly antagonistic to GH. Three genuinely hard sessions a week beats six mediocre ones you never recover from.

Respect the injury risk. Maximal sprinting is where men over 40 tear hamstrings. Bike and rower sprints deliver the same metabolic stimulus with a fraction of the risk.

Training and Fasting: Does Stacking Them Help?

Reasonable question, since both raise GH substantially.

The short version: they do stack acutely, but the combination has a real cost if you’re training hard.

Fasted training is fine if you tolerate it well and your session quality doesn’t suffer. If you’re weaker, slower and cutting sets short, you’ve traded a training stimulus for a hormone response — which, given everything above, is a bad trade.

There’s also a subtlety about what fasting does downstream that changes the calculation. We covered it fully in our breakdown of whether fasting increases HGH, and it’s worth reading before you build a protocol around fasted training.

My rule: train fed for hard sessions, fasted for easy ones if you like it. Protein and total training quality outrank hormone timing every time.

When to Train

Timing matters less than intensity, but two points are worth knowing.

Avoid finishing hard sessions within 3 hours of bed. Elevated cortisol and core body temperature both interfere with sleep onset — and the sleep-onset GH pulse is far larger than anything a workout produces.

Trading your biggest daily pulse for a smaller acute one is a poor exchange.

Morning versus evening barely matters otherwise. Train when you’ll actually train consistently. Adherence beats optimisation.

A Weekly Template

Here’s how I’d structure a realistic week for a man over 35 who wants the GH benefits alongside genuine training progress.

Monday — Lower body strength Squat or deadlift focus. 3 minutes rest on the main lift, 90 seconds on accessories. Finish with 3 minutes of hard conditioning.

Tuesday — Sprint intervals 4–6 × 30 seconds all-out, 3–4 minutes passive recovery. Bike or rower. 25 minutes total.

Wednesday — Rest or easy walk

Thursday — Upper body strength Press and row focus. Same rest structure. Finish with a short metabolic piece.

Friday — Rest or mobility

Saturday — Full body metabolic 5 compound movements, 60-second rest, 4 rounds. Hard and short.

Sunday — Rest

Three hard sessions, one sprint session, three genuine rest days. That’s enough stimulus to drive both training adaptations and a meaningful GH response, without the cortisol cost of training every day.

Common Mistakes

Chasing the pump instead of the load. Metabolic stress matters, but not at the expense of meaningful weight on the bar.

Sprinting for 10 seconds. Under-duration is the most common error in interval work. Thirty seconds feels considerably worse than you expect.

Spinning between intervals. Sit down. Active recovery reduces the response.

Training every day. Cortisol is GH’s antagonist, and overreaching produces a worse hormonal profile than training three times a week and recovering properly.

Late-night hard sessions. You’re borrowing from a much larger account.

Believing the spike builds muscle. It doesn’t. Train for the training, take the hormone as a bonus.

Frequently Asked Questions

What exercise increases growth hormone the most?

Maximal sprint intervals. A single 30-second all-out cycle sprint produced peak GH of 18.5 µg/L — over 450% higher than a 6-second sprint — and researchers describe the response as at least as reproducible as pharmacological stimulation.

Do squats increase growth hormone?

Yes. Heavy compound lower-body work reliably raises GH because it recruits large muscle mass and creates significant metabolic stress. Just be aware the spike doesn’t appear to enhance muscle growth in the trained limb.

How long should intervals be for growth hormone?

Around 30 seconds of maximal effort. Six-second bursts produce roughly a quarter of the GH response, and the effect stays elevated for 90–120 minutes after a 30-second effort versus about 60 minutes after a short one.

How much rest between sets is best for HGH?

Roughly 60 seconds. Trained men showed GH concentrations 64% higher with 60-second rest versus 120-second rest. Note that longer rest may build slightly more muscle, so choose based on your actual goal.

Does cardio increase growth hormone?

Only above the lactate threshold. Steady-state, conversational-pace cardio produces minimal GH response, though it has real cardiovascular benefits.

Does the exercise GH spike build muscle?

The evidence says no. A 15-week study found 12% muscle growth in a low-hormone condition versus 10% in a high-hormone condition, and separate work found no correlation between post-exercise GH and lean mass gains.

Should I take a supplement before training for HGH?

Be careful with arginine specifically — oral arginine taken before resistance exercise has been shown to blunt the GH response rather than enhance it, which is the opposite of how it’s marketed.

Does the GH response decrease over time?

It can. Six weeks of sprint training was found to reduce the GH response to sprinting as the body adapts, which is why progressing the stimulus and rotating modalities matters.

The Bottom Line

Here’s the honest summary.

Exercise produces the largest acute growth hormone response available to you without a prescription. Sprint intervals top the list, with a 30-second maximal effort generating over four times the response of a 6-second one.

Resistance training works too, and the biggest lever is rest interval — 60 seconds produced 64% more GH than 120. Big compound lifts, meaningful loads, short rest.

But be clear about why you’re doing it. The acute spike does not build muscle — the one-arm study settled that, with 12% growth in the low-hormone condition versus 10% in the high-hormone one.

What the GH response genuinely supports is fat metabolism, connective tissue, recovery and general vitality. For a man over 40, that’s arguably more valuable than another half-inch on his arm.

So train hard because hard training builds muscle and strength. Keep your rest short where it fits, sprint properly rather than briefly, sit down between intervals, and take three real rest days.

The hormone response comes along for the ride. That’s the right way round.

And if you’ve got sleep, training and body fat handled and want to know whether supplemental support is worth the money, our breakdown of the best legal HGH alternatives covers which formulas actually disclose their doses and which are selling you a story.

One thing to change this week: make your intervals 30 seconds instead of 15, and sit down in between. That single adjustment does more than any supplement on the market.

This article is for informational purposes and is not medical advice. Maximal-intensity interval training is demanding and isn’t appropriate for everyone — consult a physician before starting high-intensity exercise, particularly if you have cardiovascular risk factors, are over 40 and previously sedentary, or have any existing injury.

References

Exercise-induced hormones and muscle growth

1. West DWD, Burd NA, Tang JE, et al. Elevations in ostensibly anabolic hormones with resistance exercise enhance neither training-induced muscle hypertrophy nor strength of the elbow flexors. J Appl Physiol. 2010;108(1):60–67. — https://journals.physiology.org/doi/full/10.1152/japplphysiol.01147.2009
2. Full text of the above (PMC). — https://pmc.ncbi.nlm.nih.gov/articles/PMC2885075
3. West DWD, Kujbida GW, Moore DR, et al. Resistance exercise-induced increases in putative anabolic hormones do not enhance muscle protein synthesis or intracellular signalling in young men. J Physiol. 2009;587(21):5239–47. — https://pmc.ncbi.nlm.nih.gov/articles/PMC2790261
4. Mitchell CJ, Churchward-Venne TA, Bellamy L, et al. Muscular and systemic correlates of resistance training-induced muscle hypertrophy. PLOS One. 2013;8(10):e78636. — https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0078636
5. Hormones, Hypertrophy, and Hype: An Evidence-Guided Primer on Endogenous Endocrine Influences on Exercise-Induced Muscle Hypertrophy. Exerc Sport Sci Rev. 2024;52(4):117–125. — https://journals.lww.com/acsm-essr/fulltext/2024/10000/hormones,_hypertrophy,_and_hype__an.2.aspx
6. Links between testosterone, oestrogen, and the growth hormone/IGF axis and resistance exercise muscle adaptations. Front Physiol. 2020;11:621226. — https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2020.621226/full

Sprint and interval training

7. Stokes KA, Nevill ME, Hall GM, Lakomy HKA. The time course of the human growth hormone response to a 6 s and a 30 s cycle ergometer sprint. J Sports Sci. 2002;20(6):487–94. — https://www.researchgate.net/publication/11245091_The_time_course_of_the_human_growth_hormone_response_to_a_6_s_and_a_30_s_cycle_ergometer_sprint
8. Stokes KA, et al. Human growth hormone responses to repeated bouts of sprint exercise with different recovery periods between bouts. J Appl Physiol. 2005. — https://journals.physiology.org/doi/full/10.1152/japplphysiol.00839.2004
9. Stokes KA, et al. Effect of 6 weeks of sprint training on growth hormone responses to sprinting. Eur J Appl Physiol. 2004. — https://www.researchgate.net/publication/7450919_Effect_of_6_weeks_of_sprint_training_on_growth_hormone_responses_to_sprinting
10. Hsu HS. The effect of combining a Wingate sprint with circuit weight training on growth hormone in response to exercise. University of New Mexico. — https://digitalrepository.unm.edu/educ_hess_etds/14/
11. The effect of a Wingate sprint with high-intensity circuit weight training on growth hormone responses in resistance-trained young males. — https://www.researchgate.net/publication/344388743_The_Effect_of_a_Wingate_Sprint_with_High-Intensity_Circuit_Weight_Training_on_Growth_Hormone_Responses_in_Resistance_Trained_Young_Males

Resistance training variables

12. Rahimi R, et al. Effects of very short rest periods on hormonal responses to resistance exercise in men. J Strength Cond Res. 2010. — https://pubmed.ncbi.nlm.nih.gov/20555276/
13. Kraemer WJ, Ratamess NA. Hormonal responses and adaptations to resistance exercise and training. Sports Med. 2005;35(4):339–61. — https://pubmed.ncbi.nlm.nih.gov/15831061/
14. Schoenfeld BJ, et al. The effect of inter-set rest intervals on resistance exercise-induced muscle hypertrophy. Sports Med. 2014;44(12):1635–43. — https://link.springer.com/article/10.1007/s40279-014-0228-0

Intensity thresholds and aerobic exercise

15. Godfrey RJ, Madgwick Z, Whyte GP. The exercise-induced growth hormone response in athletes. Sports Med. 2003;33(8):599–613. — https://link.springer.com/article/10.2165/00007256-200333080-00005
16. Wideman L, Weltman JY, Hartman ML, et al. Growth hormone release during acute and chronic aerobic and resistance exercise. Sports Med. 2002;32(15):987–1004. — https://link.springer.com/article/10.2165/00007256-200232150-00003
17. NSCA. Growth hormone responses to stress. — https://www.nsca.com/education/articles/kinetic-select/growth-hormone-responses-to-stress/

Supplementation around training

18. Collier SR, Collins E, Kanaley JA. Oral arginine attenuates the growth hormone response to resistance exercise. J Appl Physiol. 2006;101(3):848–52. — https://pubmed.ncbi.nlm.nih.gov/16741262/
19. Forbes SC, Harber V, Bell GJ. Oral L-arginine before resistance exercise blunts growth hormone in strength-trained males. Int J Sport Nutr Exerc Metab. 2014;24(2):236–44. — https://pubmed.ncbi.nlm.nih.gov/24225560/

Supplementation around training

18. Collier SR, Collins E, Kanaley JA. Oral arginine attenuates the growth hormone response to resistance exercise. J Appl Physiol. 2006;101(3):848–52. — https://pubmed.ncbi.nlm.nih.gov/16741262/
19. Forbes SC, Harber V, Bell GJ. Oral L-arginine before resistance exercise blunts growth hormone in strength-trained males. Int J Sport Nutr Exerc Metab. 2014;24(2):236–44. — https://pubmed.ncbi.nlm.nih.gov/24225560/