When most people search for personal training prices in Naperville, they are looking at the wrong number.
They compare monthly rates, count up sessions per week, and try to figure out which option gives them the most time in the gym for the least amount of money. That math makes sense on the surface. But it misses the most important variable: whether you will actually stick with it. If you are still deciding whether you need a trainer at all, read our post on whether you should hire a strength coach first.
Here is what the research says. Half of new gym members quit within the first six months, and most are gone after just 90 days, according to the Health and Fitness Association's 2025 Benchmarking Report. Members who train with a personal trainer are 40% more likely to stay engaged and renew. And across multiple peer-reviewed studies, the pattern is consistent: shorter, high-intensity training sessions produce strength gains comparable to longer traditional programs, and people are significantly more likely to keep showing up for them.
A 2000 study by Hass et al., published in Medicine and Science in Sports and Exercise, followed 42 adult recreational weightlifters and found that single-set training produced similar strength gains to three-set programs. A separate peer-reviewed study noted that "dropout rate was higher for a multiple set program compared with one employing single sets. Twenty-five percent dropped out from the multiple set group (5 for lack of adherence and 2 for injuries) compared with none in the single set group." A third study, focused specifically on older women, confirmed the same finding: single-set protocols produced similar strength results and "shorter protocols (single-set) are associated with a higher rate of adherence" in that population.
Consistency is where most people's fitness investments go to waste, not price.
The Time Cost Nobody Calculates
At Invested Strength, clients train twice a week for 20 minutes per session. That is it. No commute to a crowded gym, no waiting for machines, no showering and redoing your hair before heading back to work. The session is private, climate-controlled, and completely focused on you from the moment you walk in. This matters whether you are a busy professional, a woman navigating hormonal changes, or an active adult who wants to keep doing the things you love.
Compare that to a traditional gym model where three to five hour-long sessions per week is the standard recommendation. When you add in the drive, the wait time, the setup, the cleanup, and the recovery from doing too much too fast, you are looking at a significant chunk of your week dedicated to something that, statistically, most people abandon before they see real results.
Time is money. Most people forget to count it.
The Equipment Difference
Not all strength training equipment is equal, and the gap matters more than most people realize.
MedX machines were developed by Arthur Jones, the founder of Nautilus, and validated through independent research at the University of Florida. According to MedX, "MedX has more scientific and evidence-based research than all other exercise equipment manufacturers combined." Traditional equipment can carry up to 30% internal friction, while MedX operates at between 0 and 5%. That means the resistance you feel is accurate, controlled, and matched to how your muscles actually move rather than fighting against a machine that is working against you.
As one MedX training resource explains, the machines "provide resistance curves aligned with tested strength profiles, operate at very low friction, and specifically and safely isolate the targeted muscle group, making incorrect movement almost impossible and reducing injury risk significantly."
For someone with joint pain, past injuries, or simply a desire to train without fear of getting hurt, that is not a small distinction.
See the machines for yourself. Your first visit is complimentary.
Schedule Your Free ConsultationA Method With a Real Track Record
The training approach at Invested Strength did not come from a certification course or a fitness trend. It came from direct instruction.
Lucas Costilow and I were trained by Tim Ryan, who has been coaching clients using this exact method since the early 2000s. Some of those clients have been training in this style for over two decades without interruption. That kind of long-term retention does not happen by accident. It happens because the method is sustainable, the sessions fit into a real life, and people feel the difference in how they move and function every day.
That lineage matters. Arthur Jones built the philosophy. Tim Ryan applied and taught it. We brought it to Invested Strength Studio.
What the Price Actually Includes
When someone calls and asks what we charge, the number sometimes surprises them. What they do not always factor in is everything that comes with it.
Every session at Invested Strength includes one-on-one attention for the entire 20 minutes. Your trainer is not watching six other clients. They are not glancing at their phone. They are with you, adjusting resistance, coaching movement, and tracking your progress from session to session. The machines are set up for you. The studio is private. There is no music competing with your focus, no one waiting for the equipment you are using, no locker room required.
Some clients rearrange their finances to make it work because they decide their health is worth prioritizing. One skipped a vacation this year, not as a sacrifice, but because she wanted to be strong and capable enough to fully enjoy every trip she takes from here on out. These are not extreme decisions. They are people who ran the math differently once they understood what they were actually comparing.
What Happens When Someone Chooses the Cheaper Option
If you find something less expensive and want to try it first, that is completely reasonable. Come in for a free consultation before you decide. Try the machines. Experience what a fully dialed-in 20-minute session actually feels like. Then make your choice with the full picture.
If the cheaper option works and you stay consistent, that is a win. But if six months from now you find yourself in the same place most people end up, having lost momentum or stopped entirely, know that the door here is still open. We stay in touch because we know the timing is not always right the first time.
Getting stronger is a long game. The best investment is the one you will actually follow through on. If you want to understand why the method works before you decide, read our post on why 20 minutes of strength training twice a week is enough.