Mixed grip deadlifts can contribute to minor asymmetries over time, but for most lifters the imbalances are small enough that they never become visible or functionally meaningful. The real concern isn’t lopsided muscles. It’s the increased injury risk to the supinated (underhand) arm, particularly the bicep tendon. Here’s what actually happens in your body when you pull with one palm facing forward and one facing back, and what you can do about it.
What Mixed Grip Changes in Your Body
When you deadlift with a mixed grip, your two arms are doing slightly different jobs. The supinated (palm-up) arm places the bicep in a lengthened, loaded position, while the pronated (palm-down) arm keeps the bicep relatively disengaged. This asymmetry extends up the chain: many lifters notice that the trap on the supinated side works harder to stabilize the bar, and the lat engagement differs slightly between sides.
A 2020 study of 29 resistance-trained athletes measured forearm muscle activity during deadlifts with mixed grip, hook grip, and double overhand at various loads. Mixed grip actually produced the least activation in the forearm muscles compared to the other grips, regardless of load or sex. That means mixed grip is efficient for holding onto the bar, but the way it distributes work is inherently uneven between your two arms. The athletes consistently ranked it as the easiest grip at every load tested.
The asymmetry in trap and lat engagement is what lifters most commonly notice. Some report that after years of always supinating the same hand, one trap appears visibly larger than the other. Whether this reaches a level anyone else would notice depends on how much of your training volume uses mixed grip and whether you ever switch which hand faces up.
The Bicep Tendon Risk Is Real
The more serious issue with mixed grip isn’t cosmetic imbalance. It’s the risk of tearing the distal bicep tendon on your supinated arm. A study published in the Orthopaedic Journal of Sports Medicine analyzed deadlift-related bicep tendon ruptures captured on video and found that 100% of the ruptures occurred on the supinated side. Not a single injury happened on the pronated arm.
The ruptures also showed a striking side preference: 75% occurred on the left side and 25% on the right, a statistically significant difference. This likely reflects that most lifters default to supinating their left hand. The mechanism is straightforward. When your palm faces up and your elbow is fully extended under heavy load, the bicep tendon is stretched and vulnerable. If the bar shifts or you reflexively try to curl the weight, that tendon can fail.
This doesn’t mean a bicep tear is likely on any given rep. These injuries are uncommon overall. But they happen almost exclusively during heavy mixed-grip pulls, and they happen exclusively on the supinated side. That’s a pattern worth knowing about.
How Much Imbalance Actually Develops
The degree of muscular imbalance depends on three factors: how heavy you’re pulling, how many sets use mixed grip, and whether you always supinate the same hand. A lifter who uses double overhand for all warmup sets and only switches to mixed grip for their top set or two will accumulate far less asymmetric loading than someone who pulls every rep mixed grip with the same hand orientation.
Powerlifting coach Dave Tate has noted that he’s never seen anyone develop a noticeable muscle imbalance purely from mixed grip deadlifts. His perspective, shared by many experienced coaches, is that the asymmetry exists but is functionally trivial for most people. Powerlifters accept it as part of the sport. For recreational lifters who care about symmetry, though, it’s an easy problem to minimize.
It’s also worth understanding that the deadlift is primarily a posterior chain movement. Your glutes, hamstrings, and spinal erectors do the heavy lifting. Your grip is just holding on. The muscles most affected by grip orientation (forearms, biceps, traps) receive a relatively small stimulus from deadlifts compared to exercises that target them directly. So even if there’s a left-right difference in how those muscles are loaded during pulls, it’s a small slice of your total training volume.
Practical Ways to Stay Balanced
The simplest fix is alternating which hand you supinate. If you pull with your left palm up on Monday, use right palm up next session. Many lifters find this awkward at first because one orientation feels more natural. That initial awkwardness fades within a few sessions, and alternating eliminates the accumulation of one-sided stress over months and years.
Another approach is limiting how often you use mixed grip at all. Pull double overhand for every set you can, and only switch to mixed grip when the bar starts slipping out of your hands. For most lifters, that means double overhand handles everything up to about 70-80% of their max, and mixed grip only comes out for the heaviest work. This dramatically reduces the total volume of asymmetric loading.
Hook grip is a popular alternative that keeps both hands pronated, eliminating the asymmetry entirely. In the same study that measured forearm activation, hook grip kept muscle engagement symmetrical across both arms. The tradeoff is significant thumb discomfort, especially early on. Many Olympic weightlifters and some powerlifters use hook grip exclusively and adapt to it over time, but it’s not for everyone.
Lifting straps are another option for training sessions where you’re not preparing for a competition. Straps let you pull double overhand at any weight, keeping your grip symmetrical while removing grip strength as a limiting factor. The downside is that your grip doesn’t get trained as hard, which matters if you compete in a federation that doesn’t allow straps.
Who Should Care Most
If you’re a competitive powerlifter, mixed grip is a practical necessity and the minor asymmetries are an accepted part of the sport. Your focus should be on bicep tendon health: avoid jerking the bar off the floor, keep your elbows locked, and don’t let the supinated arm bend under load.
If you train for general fitness or aesthetics, you have more flexibility. Using double overhand as your default, alternating your mixed grip hand when needed, or switching to hook grip or straps will keep any imbalances negligible. The small amount of asymmetric trap or forearm development that mixed grip might produce is easily offset by the bilateral work you’re already doing with rows, pullups, and other pulling movements.
The bottom line: mixed grip creates a measurable but usually minor asymmetry in muscle activation. For most lifters, it won’t produce visible imbalances. The bicep tendon risk on the supinated side, while uncommon, is the stronger reason to be thoughtful about how and when you use it.