My Canis Major (big dog) is spending his days while we're at work stretched on the couch in front of the fan. Like all of us, he slows down in the warmest weather, though we still go for our runs in the evening hours.
I'm careful, as always, to limit his intake of water after exercise to hopefully decrease the possibility of bloat (gastric torsion or gastric dilatation-volvulus) which is a life-threatening medical condition that may affect deep-chested breeds including Great Danes, who are at greatest risk. This is one of the unfortunate truths about our awesome breed. I allow Sav only a few gulps of water right after a run, and then refill his water bowl after his panting has slowed down a little, intending to spread the intake of water over a longer period. I have also heard that room temperature water is better than cold in regards to avoiding bloat, so the only really cold water Savvy gets is straight from the lake, in which case it's a little harder to control how much he drinks. He literally submerges half his head and gulps water as quickly as possible when he's extremely hot.
In other (great) news, Savage's allergies have now pretty much disappeared, at least partly due to the tablespoon of emulsified fish oil he gets at each of his two meals a day. I've been searching for a safe treatment to what I have assumed are grass allergies and sensitivity to black fly and no-see-um bites for a couple years. The problem is that once these allergies start bothering him, or insects bite him, my poor boy attempts to soothe himself by licking the affected area, which only serves to irritate it more. This causes his belly and the inside of him legs to erupt in angry red welts, and no amount of aloe I've rubbed on them will eliminate them completely. He was briefly on a steroid medication that solved the problem, but added some scary side effects. Following the prescribing vet's advice I started him on liquid fish oil and haven't looked back.
As long as he's doing well I'm content. You can see the lighter-colored marks on Puppy's belly where his bug bites had caused little scars when they healed, resulting in a change in the pigment of the fur that grew back. I sincerely wish I would have tried supplementing his diet with fish oil when I first noticed the allergies; I think it would have saved him a lot of irritation. Incidentally, fish oil has been recommended by vets for a wide range of conditions, including heart and joint health, because of the omega-3 fatty acids in it. I attribute fish oil to helping my dog, but if you are considering this treatment, please talk to your vet about dosage amounts, and keep in mind that most fish oil contains at least a measurable amount of toxic contaminants, including mercury and dioxins. You can buy so-called "ultra-refined", "cold-pressed", and "purified" fish oil. My budget allows for an emulsified (water soluble) product that is "screened to avoid toxic chemicals and metals". You may want to weigh these considerations before supplementing with fish oil, but it has worked for Savage so far, and I'm thrilled about it.

Having just drank a big dish of water on a hot day, Savvy is having some trouble getting his big, slobbery lips back in position, and is looking a little rumpled.
Incidentally, if you look closely at his bottom lip you can see a light pink spot of scar tissue - a souvenir from his run-in with a trap back in 2006.