In Parsons v. Crown Disposal Co. (1997) 15 Cal.4th 456, the Supreme Court reexamined the doctrine of primary assumption of risk in a case in which the plaintiff was injured when a horse he was riding on a bridal path was frightened by noise from a garbage truck that was operating nearby "in its normal manner." The court found that the disposal company owed a very limited duty of care to the plaintiff rider and that the company did not breach that duty. Accordingly, the Supreme Court found that summary judgment had properly been entered in favor of the defendant. ( Id. at pp. 482-485.) In reaching that conclusion, the court reviewed its decision in Knight v. Jewett (1992), then moved to a discussion of Court of Appeal decisions that had followed Knight in different contexts: "As illustrated by Court of Appeal cases decided since Knight, supra, 3 Cal.4th 296, there are circumstances in which the relationship between defendant and plaintiff gives rise to a duty on the part of the defendant to use due care not to increase the risks inherent in the plaintiff's activity. For example, a purveyor of recreational activities owes a duty to a patron not to increase the risks inherent in the activity in which the patron has paid to engage. Likewise, a coach or sport instructor owes a duty to a student not to increase the risks inherent in the learning process undertaken by the student." ( Parsons, supra, 15 Cal.4th at p. 482.)