The phrase "a heavy load on" is correct and usable in written English.
It can be used to describe a burden or responsibility that someone is carrying, either physically or metaphorically.
Example: "She felt a heavy load on her shoulders after taking on the additional project at work."
Alternatives: "a significant burden on" or "a considerable weight on".
Walking around in high altitudes is one thing, but hiking uphill, with a heavy load on your back is an entirely different game.
It was a heavy load on all those guys.
The toboggan is light in weight and will support a heavy load on soft snow.
"Because if you don't, you are carrying a heavy load on the economy that will impede your growth".
For older performance cars, consider an octane booster additive, especially if you are hauling a heavy load on a long tour.
Jump into a sack race Charging up a steep hill with a heavy load on your shoulders doesn't sound like bags of fun, but the people of Tetbury turn sack-carrying into a contest extraordinaire.
The cost of government is lower here, on average, but the mix puts a heavier load on property taxes.
Apply a heavy load of eyeliner on the bottom and liquid on top.
So while an online bot seems a little silly, the ability to free up phones and keep the website from slowing under a heavy load of traffic on a high-volume day like this could actually impact the company's bottom line – assuming, of course, that some customers actually end up using alternative ordering mechanisms, like Messenger.
Some students strategize to win, taking on a heavy load of A.P. courses, which are weighted when grade point averages are calculated.
Tom Tykwer's mathematically elegant film "The Princess and the Warrior" hangs a heavy load of metaphysical baggage on the story of a nurse in a mental hospital whose life is miraculously saved by a criminal on the lam.
